Thank you, Gabriel. Good evening, and thank you all for joining us to discuss the first quarter 2021 results of CoStar Group. Before I turn the call over to Andy Florance, CoStar's CEO and Founder; and Scott Wheeler, our CFO, I would like to review our safe harbor statement. Certain portions of the discussion today may contain forward-looking statements, including the company's outlook and expectations for the second quarter and full year 2021. Forward-looking statements involve many risks, uncertainties, assumptions, estimates and other factors that can cause actual results to differ materially from such statements. Important factors that can cause actual results to differ include, but are not limited to, those stated in CoStar's press release issued earlier today and in our filings with the SEC, including our most recent annual report on Form 10-K under the heading Risk Factors. All forward-looking statements are based on information available to CoStar on the date of this call. CoStar assumes no obligation to update these statements, whether as a result of new information, future events or otherwise. Reconciliation to the most directly comparable GAAP measures of the non-GAAP financial measures discussed on this call, including EBITDA, adjusted EBITDA, non-GAAP net income and forward-looking non-GAAP guidance are shown in detail in our press release issued today, along with definitions for those terms. The press release is available on our website located costargroup.com under Press Room. As a reminder, today's conference call is being webcast, and the link is also available on our website under Investors. Please refer to today's press release on how to access the replay of this call. And with that, I would like to turn the call over to our Founder and CEO, Andy Florance.

Thank you, Bill. Good evening, everyone, and thank you for joining us for CoStar Group's first quarter 2021 earnings call. We had a strong start to 2021 with both revenue and profit ahead of forecast. CoStar Suite had its best sales quarter since 2019 and is positioned for accelerating revenue growth into 2022. Apartments.com delivered its seventh sequential quarter of revenue growth above 20% year-over-year. Our Q1 marketing campaigns for LoopNet and Ten-X are hitting the ground running, with both businesses showing good traction. In residential, Homesnap's first quarter pro forma revenue grew over 40% year-over-year as paid subscribers more than doubled and subscription revenue grew 68%. Two weeks ago, we announced our agreement to acquire Homes.com, the next incremental step in building out our differentiated residential strategy. Overall, we remain highly confident in our ability to continue to deliver double-digit organic growth revenue for many, many years to come. Total revenue for the first quarter of 2021 was $458 million, which is a 17% year-over-year growth rate and $3 million ahead of the high end of our guidance range given in February. Quarterly sales bookings were a solid $52 million. Our profit performance was equally strong with adjusted EBITDA of $160 million, an increase of 29% year-over-year and $15 million above the high end of our February guidance. As a result, we are modestly raising our full year 2021 revenue, adjusted EBITDA and adjusted EPS guidance. But you'll hear more about that interesting news from our CFO, Scott Wheeler. CoStar Suite had its best net new sales quarter since 2019, and we appear to be moving past the pandemic disruption. We believe the combination of renewals returning to the high pre-pandemic levels, new product introductions with CMBS, STR international and Lender and the global CoStar upselling effort positioned CoStar Suite for accelerating revenue growth into 2022. Three CoStar Suite product enhancements both improve the utility of the product for all users and expand the universe of potential users. New users often sign up because of a specific feature or use case, but they often renew because of the power of the overall platform. By the end of this week, we will upload into CoStar information on over $1 trillion of outstanding commercial loans made to over 100,000 properties. Since we began including CMBS data in CoStar Suite, the supporting marketing campaign has reached the target audience with 45 million impressions and 1.3 million views of the CoStar CMBS product video. The CMBS data has helped open the doors to prospects and land multiple new accounts. The inclusion of STR's hotel data in CoStar Suite is following a similar pattern. Before STR, CoStar Suite had minimal data on hotels. Beginning on April 1, CoStar Suite subscribers received access to highly detailed data on 90,000 new and enhanced hotel properties. Since then, the STR data has been generating about 8,000 views per day. The sales force began marketing the STR data to existing clients on April 12 and is successfully adding new CoStar Suites. The next wave of sales activity will focus on targeting non-clients beginning later in Q2. The major capital flows are regularly cross-border, and one of our goals at CoStar is to align information flow with capital flow. Our strategy with international is to start a mile wide in terms of geographic coverage and several inches deep in terms of data and then continuously and consistently add depth over time. On April 22, all subscribers to our highest CoStar Suite subscription level with national coverage received access to information on 500,000 additional international properties in over 200 countries. Our plan is to steadily grow our international coverage at a measured pace over the years to come. We plan to launch CoStar Suite in Montreal, France this summer and CoStar Suite in Madrid and El Español later in this year. In 2022, we are planning to establish deeper research coverage in additional European markets, including such as Berlin, Frankfurt, Munich, Paris, Rome and Milan. If travel access to overseas markets open sooner, we may accelerate the expansion pace incrementally. In the second half of this year, we also plan to launch full global coverage of hospitality in CoStar Suite. Our goal is to track every significant commercial real estate property listing, transaction and participant possible around the world while providing customers with the best local marketing experience or cross-border global access based on their needs. Over the past 30 years, we've sold CoStar subscriptions on a modular basis with a wider range of geographical coverage options. Customers have subscribed to our property information module, a light version of our property module or a comparable sale module, or a tenant module or a suite of all the modules. 10,000 firms subscribe to just the city they operate in, with 1,000 subscribing to just the state and only a few thousand subscribing to full national coverage. We believe that as we continue to expand our geographic coverage and functionality, we can better serve our customers and create more value by offering one comprehensive global solution with all the modules included to all of our customers. Over the course of the next 18 months, we are commencing a focused effort to upsell and migrate our clients to this global suite product. The standardization of options should reduce support costs, simplify the selling process, facilitate pricing discipline, eliminate technical debt. We also believe that in providing more comprehensive value, we can also increase our renewal rates. Today, only 17% of our clients subscribe to our most comprehensive offering, so the upselling effort can create an opportunity for tens of millions of dollars in incremental subscription revenue. Decades ago, we went through a similar successful streamlining process as we moved from being a small regional company to being a national company. Now as we move into a more global footprint, we're again streamlining to facilitate growth. This strategy is similar to Bloomberg's successful comprehensive non-module offering strategy. We believe that as we offer rarely accessible accurate information on more and more segments of real estate, covering more and more geographies, our clients have consistently expanded their business into the incremental revenue opportunities we presented by giving them these broader information solutions. Through the years, I have observed many brokers who once transacted one property type in 1 or 2 neighborhoods, grow their business and then covering multiple segments across multiple cities. Previously, brokers would have simply referred deals to other brokers if it was not in their geography. But by upgrading their CoStar Suite subscription from a single market to national and international, they can now pursue these deals themselves. Once their business grows into these new broader opportunities, we become an even more important partner in their success. In early 2022, we plan to launch a powerful new CoStar product for the banking sector: CoStar Lender, an all-in-one suite for loan underwriting, surveillance, risk management and regulatory reporting tool. There are over 10,000 banks and credit unions in the U.S. with CRE exposure. And we currently do business with less than 10% of them. We believe Lender has the potential to generate over $300 million in incremental annual revenue. Lender will enable banks to link the collateral behind their loans to CoStar property and our independent market information. The product is being designed with input from U.S. regulators and includes a built-in version of the CoStar COMPASS credit default model that enables banks to forecast expected loss and probability of default for easy current expected credit loss, or CECL, reporting. The combination of increasing renewal rates, a robust new product pipeline and the simplification and standardization of the product options all position CoStar Suite for really strong accelerating revenue growth into 2022. When we acquired Apartments.com in 2014, it had less than $80 million in annual revenue and was growing at approximately 10% per year. In this first quarter of 2021, Apartments.com grew revenue 21% year-over-year, its seventh quarter in a row of growth at or above 20%. With a current run rate of over $660 million, I'm proud to say that Apartments.com is on track to overtake CoStar Suite as the largest component of our business in 2021. This strength is particularly impressive given 2 challenges created by the pandemic. The first is that the apartment owners and managers continue to operate under the budget, occupancy and cash flow restrictions of an eviction moratorium currently scheduled to expire at the end of June. And the second is that we had to suspend the build-out of our promising middle market sales team that was successfully selling into and penetrating the massive lower end of the rental market. We have launched Apartments.com's most comprehensive marketing plan ever with Jeff Goldblum returning as Brad Bellflower, our iconic spokesman and the inventor of the Apartminternet. Hopefully, many of you enjoyed our commercial Sunday night during the Oscars. Mr. Goldblum's character demonstrates the limitless lengths to which Apartments.com will go to ensure we have the most listings so that every renter can find their perfect new home. Sunday night's focus on friendly apartments is an awesome spot and a really quality piece of creative work. This year's campaign will feature 7 new TV spots and over 20,000 commercials on top prime time shows, premieres and finales as well as major sporting events, including premier placement on the Olympics this summer. Let's hope that all goes off without a hitch. We estimate the campaign will deliver over 10 billion media impressions, including twice the video-on-demand, millions of ads on streaming audio and podcast stations, including Pandora, iHeart Media and Amazon and hundreds of millions of social media and digital ads on Facebook, TikTok, Vox and Cargo as well as entering new outlets like esports and livestream on Twitch. I really believe that this is Jeff and our agency's best creative work yet, and the distribution is the most powerful we've ever deployed. I believe our Apartments.com marketing effort is operating at 214.2%. The Apartments.com network continues to make tremendous traffic gains as consumers view our advertising and experience our site. During the first quarter of 2021, the Apartments.com network, according to comScore, had 25 million average monthly unique visitors to our websites, up 4 million uniques or 21% from the same period last year. During the same period, RentPath had 9.8 million average monthly uniques to its -- for its network of sites, up only 400,000 uniques from the first quarter of last year. In other words, we have over 2.5 times RentPath's traffic and then grew our uniques by 10 times the number they grew their uniques. They continue to fall further and further behind. Zillow, interestingly, actually lost over 2 million average monthly unique visitors quarter-over-quarter. We are now ahead of Zillow by over 5 million average monthly uniques for the quarter. In the month of March, in the back of our new marketing campaign, the Apartments.com network had 26 million visitors, up 40% year-over-year, and set an all-time record for visits in a month at 78 million visits, up 45% year-over-year. As we head into the peak apartment leasing season, there are more people looking online to rent an apartment than ever before, and our share of that traffic is higher than ever before. We are continuing to see good progress in our penetration of the under 100-unit multifamily properties, both through our small and mid-market sales team based in Richmond, Virginia and our self-service e-commerce offerings to our independent owners. We define independent owners as folks who own 1 or more 1 to 5 unit properties. The revenue growth rate for buildings with 5 to 100 units has been accelerating from the low 20% range in the first quarter of 2020 to the mid- to upper 30% range in the first quarter of this year. We are excited that a portion of our 2021 marketing campaign will specifically target the massive but underpenetrated independent owners' marketplace for the first time. Our current offering of rental tools, including applications, screening, leases and payments is proving to be extremely valuable to these people. In the first quarter, over 80,000 applications were submitted on Apartments.com with credit checks resulting in over 27,000 new leases, a 14,000% increase over the same period last year. Apartments.com processed $891 million in rental payments in the first quarter, up 27% from the first quarter last year. As our marketing for these features accelerates, we look forward to expanded sales opportunities. With the now widespread availability of safe and effective vaccines, we're better positioned to restart the hiring and effective face-to-face training of new mid-market sales team members. The normalization of business use of Zoom creates much better opportunities that couple the benefits of a centralized sales force with the effectiveness of virtual face-to-face client presentations. We are still only single-digit penetrated into the vast lower end of this rental marketplace. So we believe very strongly that we have decades of high-growth runway ahead here. In the same way that Apartments.com revenue overtook CoStar Suite in 7 years, I believe Homes.com revenue could overtake Apartments.com revenue in the next 7 years. And that's not because we're expecting any slowdown in Apartments.com growth, quite the contrary. It's because the opportunity in residential is so large, our strategy is so differentiated and our assets have so much potential. We believe there's a huge gap today between how the leading portals currently leverage the digital real estate marketplace opportunity and an optimal way to leverage digital marketplaces to more effectively sell homes online. We think the current online players are overly focused on capturing agents' fees. But in contrast, we believe there's a bigger and lower-risk opportunity to facilitate selling homes faster and with greater certainty by digitally empowering the established and entrenched channels. We recognize and are comfortable with the fact that our initial market position is, in fact, modest today. Two weeks ago, we announced our agreement to acquire Homes.com from Dominion Enterprises. Back in 2018, Dominion sold us ForRent. Thank you, Rusty. Members of the ForRent team became key members of our Apartments.com team that helped build that business. Homes.com will similarly bring with it a talented team of managers and an excellent intuitive URL with an existing base of residential traffic. We believe that our plans to combine Homes.com, Houses.com and the agent marketing and workflow tools of Homesnap and even CoStar will create the foundation of a differentiated solution to offer a much better alternative to the old, first-generation real estate web portal models. Not sure where to put it in the call but somewhere, you have to admire, at least appreciate, the branding benefit of how Homes.com meets -- or fits with Apartments.com. Apartments.com, Homes.com, Homes.com, Apartments.com, there's some serious marketing in their heels. I'm very pleased to report that LoopNet is crossing the $200 million revenue run rate milestone right now and continues to enjoy robust traffic growth with 34% quarter-over-quarter growth in unique visitors to the site. The site reached a record 10 million unique monthly visitors in March. LoopNet sales continue to show strength in an adverse commercial real estate market in the first quarter, with revenue growing 14% over Q1 2020. The year-over-year growth number was negatively impacted by the depressed subscription sales for LoopNet last year during the chaos of the first couple of months of the pandemic. However, during the first quarter of 2021, we saw significant growth in our higher-tier advertising solutions, with Diamond, Platinum and Gold ads growing 50% over the same period a year ago. Demand for prominent placement with these higher-tier ads on LoopNet is strong as average listing prices for these ads grew to $984 a month average in Q1 2021, up from just $710 a month Q1 2020. Year-over-year revenue growth for our high-volume, lower-tier Silver ads was only 6%, which is how we like to manage volume ads to avoid saturation and internal competition with CoStar. We ended the quarter on a strong note in the month of March with our third-highest monthly net bookings result. Pandemic restrictions this past year have made it difficult to effectively onboard and train additional sales resources to sell LoopNet. If you have any children learning from home during the pandemic, you know what I mean, and you can appreciate how ineffective Zoom-based school can be. Fortunately, with the ability to return to the office and travel, we plan to start adding sales resources later this quarter to accelerate LoopNet's growth further. Even before that, we were still able to achieve an outstanding sales result in March by cross-commissioning and incentivizing our large, experienced, general commercial real estate sales force to sell LoopNet. Mark and Drew did a good job making that happen. We are seeing more and more of these sales professionals put up impressive sales results in both LoopNet and CoStar simultaneously. We continue to make significant enhancements to LoopNet's e-commerce sales channel. The e-commerce LoopNet sales contribution is growing and increased 24% Q1 '21 over Q1 '20. With the pandemic's negative impact on commercial office leasing, the availability rate for office space has jumped 400 basis points over the pre-pandemic availability rate. The availability rate as a percentage of office space being actively marketed for lease is the highest level we've ever recorded. We believe that makes LoopNet's reach to millions of tenants searching for commercial real estate more valuable than ever to owners who need to find tenants to fill their vacancies. It couldn't be more important. As such, we're maintaining our plans for increased investments in marketing LoopNet to owners, brokers, investors, and tenants. The "Are you in the Loop?" campaign we ran from February through March this year targeted brokers and owners in an effort to elevate the LoopNet brand to top of their mind. That campaign generated 58 million impressions of high-impact creative across a variety of direct media partners, social media channels as well as programmatic video and display partners. The initial campaign served as a teaser to our broader $20 million campaign launching this May called Space for Dreams, which targets tenants and reinforces LoopNet as the most popular place to find a space. We're working with this on RPA, the agency we used to produce the excellent Apartments.com work, to produce this upcoming campaign. They have tapped Niall O'Brien as director, an accomplished director and fine arts photographer, who captures the pride of ownership inherent within buildings and showcases the breadth of buildings on the LoopNet marketplace. Niall has the ability to capture buildings in their best moment and bring the design intent of the architects to life. He creates an excitement around the properties and the opportunity they represent. The intention of this campaign ranked through the rest of the year across broad-based media is to continue to elevate the LoopNet brand and increase brand awareness. While the campaign targets tenants, we're really actually targeting owners and brokers as a pass-through audience. We believe the striking high-end architectural imagery will resonate with owners of ultra-high-value properties and position LoopNet as a brand-appropriate channel for high-end, high-dollar property advertising. All this so I can tell Scott that our ASP per ad is going up. We have put in place many foundational elements for LoopNet to succeed this year and in the years to come. We can clearly see the enormous scale of this opportunity. Though we're crossing a $200 million revenue run rate milestone, our penetration rate is still only a low single-digit number. There are tens of thousands of very high-value opportunities out there for us and hundreds of thousands of value opportunities overall, and we're focused on winning those opportunities and growing this business. Ten-X delivered another solid quarter and continues to benefit from the CoStar and LoopNet driving potential buyers to Ten-X. Ten-X's unique monthly visitors rose 45% quarter-over-quarter. On a year-over-year basis, overall account creations increased 61% with CoStar/LoopNet source creations up over 1,000% from 330 to 3,700. Average registered bidders per property rose from 5 to 13, a 160% increase; and average live bidders per property increased from 2.5 to 4, a 68% increase. The growth in the number of bidders is key because when there are 3 or more bidders at an auction, there's an 85% probability of transacting. That's an excellent number that draws properties to our network. As a result, in March, the trade rate, the percentage of properties that came to auction and sold, hit an all-time high of 81%. These strong metrics are excellent proof points of the network effect from combining Ten-X with the CoStar platforms. During the first quarter this year, we grew our Ten-X sales teams by 39%, launched a best-in-class 6-week sales training program and lead generating training program and capitalizing on this growing momentum by launching a new national marketing campaign called Ten-X It, starring comedian Keegan-Michael Key, a great actor. We believe this campaign will further establish Ten-X as a leading brand for online commercial real estate transactions, drive market awareness that there's no faster or more certain way to exchange commercial real estate and that Ten-X as a part of the CoStar network will become an exponentially better way for buyers, sellers, and brokers to exchange commercial real estate. As the campaign says, "Why just buy it or sell it when you can Ten-X It?" The successful vaccine rollout across the U.S., combined with fiscal stimulus, high household savings rates, relaxed COVID restrictions, and warmer weather, have boosted consumer sentiment and spending, helping the labor markets, retail sales, restaurants, service industries, and travel. The office sector struggled in Q1, setting a record for the largest single quarter of negative net absorption. Overall leasing activity remains depressed. Many companies are still evaluating their workplace strategies, but in-person tours are restarting. I'm doing one first thing in the morning. And vaccinated workers are gradually returning to in-person environments. For multifamily, the defining trend of 2020 was weak demand in the densely populated urban centers and strength out in the suburbs. While the first quarter couldn't be described as a reversal of that trend, demand has recovered to normal levels in urban centers while staying strong in the suburbs. Record search activity at Apartments.com reflects continued strong multifamily demand. Fiscal stimulus and improving health conditions are helping the retail sector, especially the service sector tenants that have struggled with lower foot traffic over the past year. Hotel occupancies continue to improve by leisure travel and are hurt by continued weak business travel. The industrial sector continues to outperform and set new quarterly leasing volume records driven by the double-digit acceleration of e-commerce. Despite the wave of new construction in the industrial sector, vacancies there ticked down in Q1 and remained near all-time lows. The capital markets have rebounded on the back of strong portfolio trading activity and a return of large national buyers. With record levels of dry powder, investors are on the lookout for distressed opportunities, so far concentrated on hotels with expectation for distressed retail assets to follow. We just need to make sure they Ten-X those opportunities instead of just buying them. Last March, as you know, we quickly evacuated all of our offices, and our staff moved to safely work from home. Our team did an outstanding job. And though it was difficult, they all made it work for our clients, our shareholders, and one another. With safe and effective vaccines now widely available, and with the help of a number of CoStar Group organized vaccine clinics on site, more and more of our staff are now vaccinated. I believe it's the majority. Employees are now safely returning to our offices by the hundreds. While it's early days, it feels like we're moving towards a more normal and productive 3D, real, face-to-face, collaborative workplace we used to enjoy. I believe that companies with teams that are able to work together face-to-face will always outcompete remote, dispersed teams. Our offices feel like a return to a college campus after a long, long summer break. I see thrilled colleagues smiling behind their masks when they run into close colleagues they've not seen in ages. It's really quite nice to see.

Thank you, Andy. I'll be using my 3D voice today. So hopefully, you'll notice the difference, all of you who are listening. Last year, I used my 2D voice. But yes, I think that the last part is the best news of all of everything you talked about: going back to our offices, rolling out vaccines to protect our teams and their families and getting to welcome our friends and our team members back to our offices every day. It really is super fun. And we had a great first quarter financially. I'll call it hitting through the cycle with double-digit growth in sales bookings, revenue, adjusted EBITDA, and non-GAAP EPS. We included Homesnap, currently in their rookie season with CoStar, in our financial results for the first time this quarter, and they were great. And we also signed up a strategically important prospect in the online residential spaces, Homes.com. So onto the results. Revenue in the first quarter 2021 increased 17% over the first quarter of 2020, which is above the high end of our guidance range. The organic revenue growth in the first quarter, which excludes Homesnap and Ten-X, was a strong 11% year-over-year as we've come around to 1 year after the start of the pandemic. Going forward, we expect organic revenue growth to improve to approximately 12% to 13% for the second quarter and for the remainder of the year. CoStar Suite revenue grew 4% in the first quarter of 2021 versus the first quarter 2020, at the high end of our expectations. As we begin to lap the low sales months that began in March 2020 as a result of the pandemic, we expect to see CoStar Suite revenue growth improve sequentially, CoStar Suite sales in the first quarter of 2021, along with contract renewal rates, return to pre-pandemic levels. So this is certainly very encouraging and is a much faster recovery than what occurred in the last recession for CoStar Suite. We expect CoStar Suite revenue growth in the 5% to 6% range for the second quarter of 2021. Revenue in Information Services grew 7% year-over-year in the first quarter of 2021 to $35 million. Both the Real Estate Manager and STR turned in strong double-digit subscription revenue growth in the first quarter with Real Estate Manager subscription revenue up 19% and STR subscription revenue up 15% compared to the first quarter of 2020. The strong subscription revenue growth was moderated somewhat by that drop in transaction revenue, which is the one-time revenue in STR that dropped, which occurred in the first part of the pandemic, in the first quarter of last year. Overall, we expect revenue growth for Information Services to improve sequentially to a rate of 12% to 14% in the second quarter of 2021, and we continue to expect growth of 10% to 12% for the full year. Multifamily revenue growth for the first quarter remained strong at 21% compared to the first quarter of 2020, which is at the high end of our expectations. The number of properties advertising with us was up 10% in the first quarter, with growth in the average rate per property also up around 10% as properties continue to upgrade their advertising packages and increase our exposure. The mid-market revenue growth rate was up over 35% in the first quarter, as Andy mentioned, with growth balanced pretty evenly between the growth in number of paying properties and growth in the revenue per property. We expect revenue for multifamily to grow at the rate of approximately 18% to 19% in the second quarter of 2021 compared to the second quarter of 2020. Commercial property and land revenue grew 48% year-over-year in the first quarter, in line with our expectations. This includes the impact of the Ten-X and Homesnap acquisitions. Organic growth was 11% year-over-year in the first quarter. We expect the reported commercial property and land revenue growth rate to be approximately 55% to 60% for the second quarter of 2021. Organically, we expect growth of approximately 18% to 20% for the second quarter with improved growth across all of the marketplaces in the sector as we lap the initial pandemic impact from last year. Within commercial property and land, LoopNet revenue showed solid growth in the first quarter, increasing 14% compared to the first quarter of 2020, just a touch below our expected range of 15% to 16%. But it's been difficult to effectively onboard and train additional sales resources to sell LoopNet during the pandemic, as Andy referenced. We expect LoopNet revenue growth to improve sequentially and grow approximately 19% to 20% in the second quarter. Our gross margin came in at 81% in the first quarter of 2021, in line with our expectations, and we expect gross margins to continue at that level in the second quarter with gradual improvement throughout the end of the year. Our profitability was strong in the first quarter with net income, adjusted EBITDA, and non-GAAP EPS results all ahead of the guidance we issued in February. Net income was $74 million in the first quarter with an effective tax rate of 20% for this quarter. The first quarter effective tax rate was higher this year compared to the first quarter of last year, and that's due to fluctuations in the amount and the timing of share-based payment deductions. Those wacky share-based payment deductions, you just don't know what they're going to do. First quarter adjusted EBITDA was $160 million, up 29% from the first quarter of last year, and came in approximately $15 million above the high end of our guidance range. The improved adjusted EBITDA was primarily the result of higher revenue, lower personnel expenses, and timing variances in the number of operating expense categories across the P&L. The operating expense favorability is primarily timing, and we expect to incur some of those expenses later in the year. The resulting adjusted EBITDA margin of 35% in the first quarter was 320 basis points above the first quarter of last year. Now we'll talk about some of the performance metrics for the quarter. At the end of first quarter, our sales force totaled approximately 835 people, which is lower than the sales force number reported at the end of 2020 by approximately 65. Part of this reduction is actually a modification of how we count direct sales. So a little bit of a restatement, if you would. We moved approximately 25 positions out of the sales count in the first quarter, positions that are focused on account management or managerial responsibilities that don't really directly impact sales. So the remaining decline in sales headcount sequentially of around 40 people is from first quarter attrition in the CoStar and LoopNet sales teams primarily which, from a timing perspective, was not replaced in the first quarter given the difficulty of hiring and training new sales resources while we work remotely. We expect to not only replace but to increase the size of both the CoStar and LoopNet sales teams this year. The renewal rate on annual contracts for the first quarter of 2021 was 90%, unchanged from the fourth quarter of 2020. The renewal rate for the quarter for customers who've been subscribers for 5 years or longer was 96%, a slight improvement from the renewal rate of 95% in the fourth quarter of 2020. Subscription revenue on annual contracts accounts for 78% of our revenue in the first quarter, which was in line with the last quarter. Before I talk about the second quarter and our revised outlook, let me say a few comments about the pending Homes.com acquisition, which we have not included in our outlook for 2021. Today, Homes.com generates approximately $10 million in revenue per quarter, and it's not profitable. Subject to the deal closing, which we expect to happen by the end of the second quarter this year, we intend to evaluate existing product revenues and discontinue certain services that are inconsistent with our strategy. As we wind down these services and record typical acquisition accounting adjustments, we expect to record approximately $5 million to $10 million in revenue for Homes.com in the second half of this year. We're too early in the process to provide specific guidance on the profit impact to our business. But at a high level, I would expect the transaction to be just modestly dilutive to earnings in the second half of the year as we work through integration. I'll now talk through our outlook for the full year and the second quarter of 2021. We expect full year revenue in the range of $1.930 billion to $1.945 billion for 2021, which implies an annual growth rate of 17% at the midpoint for the year. On an organic basis, excluding the impact of the Homesnap and Ten-X acquisitions, we expect growth of approximately 12% to 13% for the full year 2021. For the second quarter, we expect revenue in a range of $465 million to $470 million, representing revenue growth of 18% year-over-year at the midpoint of the range. For the full year 2021, we are raising our outlook for adjusted EBITDA to a range of $645 million to $655 million, which implies an adjusted EBITDA margin of 33.5% at the midpoint of the range. We expect adjusted EBITDA of approximately $130 million to $135 million in the second quarter of 2021 for an adjusted EBITDA margin of between 28% and 29%. Our marketing campaigns for Apartments.com, LoopNet, and Ten-X all accelerate in the second quarter, which results in the lower sequential margins, which isn't the case in most years. Our marketing spend in the third quarter is expected to remain at or near second quarter levels before dropping back down into the fourth quarter. So overall, it was a great start to the year. And even better, I'm fully vaccinated, Andy is fully vaccinated. We're very excited to see 3D people here in our office. But Bill here, he's still in 2D. We're going to call him flat Billy. All right, Billy, back to you. We're going to let you open it up for questions from the flat analysts on the call.

Thank you very much, Scott. Gabriel, could you please gather the questioners for the queue?

I guess I'm going to have to accept being 2D for now. Andy, residential, obviously, has grabbed a lot of attention, right, just last quarter or 2, what was CoreLogic and all. Could you elaborate, I guess, a little bit beyond the relatively small deals you've done, albeit important, in terms of how you intend to build that out? Do you need to buy data? Do you need to buy a database? Are you going to build the database? Just trying to think about how you get from Point A to Point B in that big TAM.

Yes, we already have a strong position with Homesnap, which connects us with many key industry players who can provide the access we need. We subscribe to various residential information sources, and we believe we can collaborate with Homesnap and Homes to create a compelling strategy. We expect to receive significant support from market participants for this strategy. While first-generation models have operated at scale for a while without generating substantial profits, we see an opportunity to create a more profitable, lower-risk model by utilizing a different approach. Instead of taking agent fees, we aim to leverage the Internet's reach to connect buyers more efficiently and reliably. We are in the process of developing this plan and will continue to refine it in the coming months, with plans to roll it out later in the year. I don't see the need for additional acquisitions to implement this strategy right now, although future opportunities may arise to support our plans. We are content with our current strategy focused on the cost-effective Homes.com. As a lighthearted note, we may have overpaid for it, but negotiations with the seller are ongoing and challenging.

Andy, you outlined a lot of growth initiatives in your prepared remarks. And I guess what I need to better understand, or help me better understand, how do each of those ramp in the timing because it seems like there's a lot of opportunity where I think investors are going to wonder are you going to accelerate that organic growth and to what extent and over what time frame?

Yes. Much of this is somewhat dependent. I know you have kids, and some of them may have been homeschooling for a while, which is not as effective as in-person schooling, especially when starting a new school. It's been challenging to build sales teams effectively during this period. As we begin to return to a more normal state, I'm eager to build those sales teams effectively. There is an opportunity to accelerate growth in Apartments. Our marketing engine is functioning well, especially at the middle and lower ends, and it just needs more sales resources to support it. The LoopNet product is performing well and could also see increased growth with additional resources. I'm excited about the centralized, advanced virtual selling opportunities that technology presents. The CMBS launch is on track, with a global rollout expected to begin in the next quarter. The hospitality launch is also planned, and for Ten-X, we have successfully captured demand, increasing registered bidders from 4 or 5 to 13. We now need to increase supply, which is where the revenue will come from. We have started training researchers to generate leads and have a solid training program in place. We are working on building the sales force there, which should contribute to growth. Everything seems to be coming together as we approach the middle of the year. I appreciate Pfizer, Moderna, and J&J for their roles in supporting our growth. Regarding CoStar Lender, that is an excellent product with great potential, and we have a strong team, led by John McKaron. The timeline for that launch has shifted from the fourth quarter of 2021 to the first quarter of 2022, as it's a complicated product but very promising. So that one is more of a 2022 initiative.

CoStar Suite had its best sales quarter since 2019, and that was helped by new product enhancements. Can you talk about what the sales strength reflects in terms of whether it's new institutional customers that are being brought on versus penetration among brokers versus increases in pricing that's coming back?

Yes. I don't believe there is any significant impact from pricing increases, as no pricing increases are occurring at this time. Looking ahead to later in the year, I think we will see increases in average purchasing amounts. Customers are likely to move from one module to three modules as they transition to the global suite, which will effectively increase revenue per customer. Currently, we are experiencing higher renewal rates. The decreasing cancellation rate significantly impacts our business as people feel more secure about their operations and see positive signs for the future. Additionally, there are likely to be more seats from existing institutional clients. The CMBS data is proving to be very valuable in our offerings, and the STR data is particularly popular among those working in hospitality. Our reasoning for acquiring STR was that it was a well-regarded product among hospitality operators and investors, but it lacked a distribution channel to those involved in appraising, brokering, and developing hotels. We have been able to bring their product to market efficiently, which has been a significant advantage for us. Would you like to add anything?

Yes. I think, George, when you look at the stats on CoStar usage right now, as far as subscriber numbers, this is the first quarter we went over 160,000 subscribers. So certainly, after the dip in the second quarter last year, it's been coming back well. And as Andy said, clients are adding seats and adding users, particularly to take advantage of some of the new information. When you look at the number of sites that are using CoStar, that's also at a high level now that we hadn't hit before, over 38,000, 171 sites, it's right up at the top of where we've been. And then when you look at the number of new subscribing firms coming on, this quarter was as big as it was right after we did Xceligent, that was in bankruptcy. So like the second quarter of 2018 after that first peak, we had some pretty high levels, but now we're adding again at those levels at average contract sizes that are probably 30% higher than what they were back then. So you just kind of look at whether it's sites, whether it's subscribers or whether it's users, all of them are rising across these different customer sets.

Really nice trends here. Andy, I really appreciated the Homes.com-Apartments.com comparison. I thought that was pretty interesting. But certainly, looking back to that era, Apartments.com acquired a ton of marketing investment, and I think it was $150 million in its first year. Should we expect that type of aggressiveness in scaling Homes.com at some point?

We currently do not have a specific plan regarding that. There are no analyses of such investments on Scott Wheeler's desk. We are exploring the broader opportunity. From my perspective, the residential opportunity feels repetitive. We have several backend systems supporting the front-end real estate marketplace, and we've been doing this for many years. As LoopNet exceeds $200 million and Apartments becomes our largest segment, it resembles our previous efforts. With this, we invest in marketing. If you're watching Squawk Box, you might notice a Ten-X ad followed by a LoopNet ad and later an Apartments.com ad on Peacock. This is part of our strategy, and typically, we invest in marketing ahead of revenue. As we pursue an opportunity that could eventually generate billions in additional EBITDA, it will require capital from our shareholders to realize that potential. We may eventually utilize the resources our shareholders have provided. However, it's a multi-year effort, starting primarily with software, which may not be immediately apparent to analysts or shareholders.

So you mentioned that signature ads were up about 50% in the quarter. I think that was about similar to 2020. So do you expect the new marketing campaign and the step-up in the sales force to accelerate growth this year? Just wondering, besides the marketing campaign and the sales force additions, what are the other key levers to accelerate this?

Yes, we anticipate that LoopNet's year-over-year sales will quickly return to around the 20% growth mark. If we successfully add salespeople who are effective in this area and our existing commercial real estate sales team continues to sell both CoStar and LoopNet, we expect to see significant acceleration. We are gaining real interest from high-end clients who previously perceived LoopNet as primarily focusing on lower-end or suburban properties. Our marketing efforts are now targeting high-end properties valued at $1 billion, which should create many new opportunities. Currently, we have only penetrated 3.8% of our high-target prospects, which number over 50,000 and represent substantial monthly sales opportunities. Increasing this penetration to 20% through focused sales strategies and targeted marketing could greatly enhance our revenue growth. We have a solid strategy, and it’s about fine-tuning the various elements.

A question to margins. Given the investment priorities and the growth initiatives, what are some of the levers you have to increase margins and get that 40% targeted goal by 2023 and how you're taking change in terms of that target and how you even get there, given the change in the cost structure in the midst of the pandemic?

Yes. As we look ahead to 2023, we expect organic growth to rebound, particularly with CoStar experiencing its lowest quarter in Q1 and then improving for the remainder of the year. This will lead to an increase in organic revenue growth. We plan to add revenue in modest ways through acquisitions. Our current cost structure allows for a decision-making approach to investment each year, meaning we can continue to grow our costs by around 8% to 10% or slightly more over the next few years, and that revenue growth will enhance our margins. It's crucial to leverage our fixed costs while maintaining and increasing organic revenue growth, which is made possible by the investments we've made over the past year and into this year. These investments provide the necessary support for revenue growth, and we will be vigilant in managing cost growth within the 8% to 12% range over the next couple of years, aiming for that 40% margin target. We've already significantly ramped up our marketing efforts this year with major campaigns for Ten-X and LoopNet, having done something similar last year for Apartments. Even with these substantial marketing increases, we can still improve our margins. The scale of our business and its leverage now empower us to pursue initiatives that would have been risky and detrimental to our profits in the past, but now they have a minimal impact, giving us considerable flexibility across all our sectors.

Just in terms of M&A, it's hard to ignore the cash balance and the balance sheet. So you said publicly recently that you intend to focus on acquisitions in areas which CoStar does not directly compete meaningfully today. And it's clear that residential is going to be a part of that playbook. But maybe you can elaborate on other areas of the business that you see as potentially being synergistic with the broader CoStar portfolio. For example, I believe, in the past, you've referenced areas like workflow and facilities management software as examples.

Sure. We have completed three deals this year so far, and I expect that we will keep evaluating various opportunities. These opportunities come from a wide range of sectors, including facilities, which we are definitely looking into, as well as numerous residential options, most of which are domestic, with ForRent being a small exception. It's generally challenging to discuss specific details before they materialize, and recently, we've been focusing on smaller deals. Currently, there are about 20 potential deals on our radar. The last few we've completed have been modest in size, although there was one that had significant potential. We are reevaluating and concentrating on many opportunities. I have no doubt that CoStar will maintain its consistent approach from the past 30 years, focusing on strategies that align with our current initiatives while also adding to the larger themes we’re pursuing. Residential represents a substantial theme with ample opportunities, and I can say that the influx of deals is remarkable. I’m seeing about three opportunities on my LinkedIn daily. Overall, it's more of the same, but we are proceeding with a measured and steady approach. Would you like to add anything to that?

As you say, the residential pipeline has thrown everything at us right now. We still see things coming in the apartment sector quite frequently and commercial real estate and small information plays. There will still be others internationally that are coming at us. So all the things we've talked about before are still very active. But residential has just added another dimension and higher volumes, a lot to sift through.

So I wanted to talk about the new salespeople you're adding. And maybe you can just talk about the timing to productivity for these new salespeople. You're building out the middle market team, the LoopNet team, Ten-X. I mean we've heard other companies within the information services space talk about, say, a 3-year timeline. And so they hit their max productivity. Do you guys have an idea of what that looks like for these new hires? And then also, because of what we're seeing in the labor market with the government support and stimulus, there's been commentary from a lot of other companies saying that it's been hard to hire, basically competing against the government. Is that a concern of yours at all? And does that create any type of wage inflation or an increased labor expense or comp expense for you?

Your observation about competition with the government for employees is correct. This issue is more prevalent in the restaurant and some service industries, where I hear about people being unable to hire because there are better-paying jobs with the government. In terms of hiring, my focus is on a centralized sales effort. We have strong field sales teams for Apartments and CoStar, and I am looking at a centralized approach for efforts like Ten-X, mid-market Apartments, and LoopNet. I have recruited experienced trainers and leaders to Richmond, giving us an edge to compete for talent there. We are also investing more than ever in our training programs. We are introducing 6- and 12-week training programs with the goal of achieving a higher success rate. For LoopNet, we think new hires can be onboarded and begin selling within 3 months, while Ten-X might take 6 months, and Apartments about 3 months. In terms of peak efficiency, we expect new hires from LoopNet and Apartments to reach full production levels in about 18 months, while Ten-X might take 24 months. However, if we can onboard them within the first 3 to 6 months, we have a clear understanding of their return on investment, which is substantial. We have a wealth of prospects in our database and understand their marketing needs, with many more prospects than our current team can reach. Our offering is highly differentiated, and our ability to identify potential customers is excellent. I look forward to a time where there is less competition from the government for our sales force.

On the CoStar Suite, the global platform, I guess, what percentage of your CoStar Suite subscriber base do you think could be interested in this? And what could the revenue uplift potentially look like over the next years if you're able to drive meaningful adoption?

There are several things happening. First, we're really focusing on upselling modules to customers who are purchasing information on properties and getting tenant comparisons, along with more overall functionality for the city they operate in. This creates thousands of upsell opportunities. Next, many customers are just getting data for the cities they operate in, which seems short-sighted since a significant portion of their clients come from out of town; they should be aware of what's happening outside their local market. When we expand globally, we'll engage more with private equity firms, institutions, and cross-border investors. For high-end properties in places like New York or London, over 50% of the capital comes from abroad, and we believe we can offer those investors a unique service. This opportunity spans from small to large clients, potentially generating hundreds of millions in revenue. More importantly, it positions CoStar Group transformatively. Currently, commercial real estate professionals in cities like London or Toronto view our solutions as localized; however, I believe developing a robust pan-European product will change perceptions at the local level. If I reflect on the last 10 to 20 years, our value proposition has evolved significantly as we've expanded our coverage from a few U.S. cities to all major markets, resulting in exponential value growth for the users. We're concentrating on enhancing investment sales tools, comparable sales tools, and international news, which should alter our market perception and positioning. Although I’m not sure if I fully answered your question, I wanted to share my thoughts on international expansion and suite upselling. It's an exciting time for us.

It sounds like a lot of the consolidated net bookings growth was in Suite. I caught a lot of metrics on Apartments' traffic and lead quality and revenue, but I don't think I caught Apartments' net bookings trends, so would love some detail on that or, if not, maybe just a random stream of consciousness on something else.

Do you want to do a random stream of consciousness? Yes, we didn't talk specifically about Apartments' sales. But I mean you can do the math on our total sales numbers and kind of assume if CoStar goes up quite a bit, we're going to have like other sectors that will come down a bit. LoopNet stayed strong. Information Services stayed strong. And I'll say the volatility in Apartments is within the range of volatility it does every quarter. So it happened to be down a bit this quarter. But if you look back over the last 10 quarters of Apartments sales, which appreciate, Jeff, we don't give these numbers because of this fact, because they are volatile, Apartments net bookings move up and down, on average, $5 million between each quarter. So you'll see this kind of up and down in the pattern. But over time, the growth obviously is there because we're still pushing the thing at 20% revenue growth. So we had such good quarters mid- to late 2020 in Apartments. I think property owners have used a lot of budget then. They trimmed them back a little bit in the first quarter, waiting for the second quarter season mostly, and then seeing where they're going to be positioned when we come back to these moratoriums, the eviction moratoriums. So you saw a little hesitancy, I think, in property owners in the first quarter, which moderated the Apartments side a bit. But CoStar picked up the slack.

Can you discuss the economics CoStar gains from the rental payments made through Apartments.com? Will this lead to a larger opportunity, or is it primarily about the tools you are providing to these users?

Yes. I'll let you address it; it's similar to a credit card that we're acquiring.

Yes, we get a few small percentages off of the cards. We don't get anything else to ACH-type payments. So you get a little bit of margin off of the payment tools. And it keeps people on the platform month-to-month, which is what's really important when they filled up their units. It's not intended to be a primary revenue driver for us but one of the tools that drive the advertising and the other services.

As the revenue grows into the tens of billions or $100 billion, it will become significantly more impactful. We do provide an ACH acceleration service for which there is a fee, but only a small fraction of users take advantage of that. The larger value for us comes from owners who appreciate our applications, payment options, and renewal tools. These users are often willing to invest in a $200 or $300 online ad to improve their visibility, which far outweighs the earnings from the credit card or ACH acceleration fees. This potential revenue from them purchasing the complete suite of services we provide presents a multibillion-dollar opportunity with higher margins. Thus, our focus is on expanding our membership base on our platform. Additionally, more engagement leads to a more vibrant marketplace, attracting more renters and advertisers. This is part of an interconnected process. We have long believed that offering a comprehensive range of services to independent owners, who typically lack the resources to manage these functions internally, is essential.

And we have no further questions at this time. I'll turn the call back over to the presenters for closing remarks.

Well, we appreciate you joining us for this first quarter 2021 earnings call, and we look forward to updating you on our progress. We obviously have a lot of stuff going on. And I think we may be appearing optimistic, and that is how we are. So thank you very much for joining us. We look forward to talking to you again.

This concludes today's conference call. Thank you for joining. You may now disconnect.