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CoStar GroupMIL:1CSGP 57 Shiller PE Ratio is 40.55 as of Aug. 15, 2026, which is 80% below its 10-year median of 200.06. GuruFocus rates MIL:1CSGP with a GF Score™ of 57/100 and a GF Value™ of €85.00 (Significantly Undervalued). The stock has 2 warning signs investors should review. Among 1,036 Real Estate companies, CoStar Group ranks worse than 88.32% on this metric.
As of today (2026-08-15), CoStar Group's current share price is €26.76. CoStar Group's E10 for the quarter that ended in Jun. 2026 was €0.66. CoStar Group's Shiller PE Ratio for today is 40.55.
The historical rank and industry rank for CoStar Group's Shiller PE Ratio or its related term are showing as below:
MIL:1CSGP'
s Shiller PE Ratio Range Over the Past 10 Years
Min: 39.51 Med: 200.06 Max: 295.83
Current: 46.31
During the past years, CoStar Group's highest Shiller PE Ratio was 295.83. The lowest was 39.51. And the median was 200.06.
MIL:1CSGP's Shiller PE Ratio is ranked worse than 88.32% of 1036
companies
in the Real Estate industry
Industry Median: 11.605
vs MIL:1CSGP: 46.31
E10 is a concept invented by Prof. Robert Shiller, who uses E10 for his Shiller PE Ratio calculation. E10 is the average of the inflation adjusted earnings of a company over the past 10 years.
CoStar Group's adjusted earnings per share data for the three months ended in Jun. 2026 was €0.122. Add all the adjusted EPS for the past 10 years together and divide 10 will get our E10, which is €0.66 for the trailing ten years ended in Jun. 2026.
Shiller PE for Stocks: The True Measure of Stock Valuation
CoStar Group (MIL:1CSGP) Shiller PE Ratio Explanation
Compared with the regular PE Ratio, which works poorly for cyclical businesses, the Shiller PE Ratio smoothed out the fluctuations of profit margins during business cycles. Therefore it is more accurate in reflecting the valuation of the company.
If a company has consistent business performance, the Shiller PE Ratio should give similar results to regular PE Ratio.
Compared with the PS Ratio, the Shiller PE Ratio makes the comparison between different industries more meaningful.
Be Aware
Shiller PE Ratio assumes that over the long term, businesses and profitability revert to their means. If a company's business model does not work in the future compared with the past, Shiller PE Ratio and PS Ratio will give false valuations.
CoStar Group Shiller PE Ratio Related Terms
CoStar Group Shiller PE Ratio Historical Data
* Premium members only.
The historical data trend for CoStar Group's Shiller PE Ratio can be seen below:
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
MIL:1CSGP vs COMP, JLL, BEKE: Shiller PE Ratio Comparison
For the Real Estate Services subindustry, CoStar Group's Shiller PE Ratio, along with its competitors' market caps and Shiller PE Ratio data, can be viewed below:
* Competitive companies are chosen from companies within the same industry, with headquarter located in same country, with closest market capitalization; x-axis shows the market cap, and y-axis shows the term value; the bigger the dot, the larger the market cap. Note that "N/A" values will not show up in the chart.
CoStar Group Shiller PE Ratio vs Real Estate Industry
For the Real Estate industry and Real Estate sector, CoStar Group's Shiller PE Ratio distribution charts can be found below:
* The bar in red indicates where CoStar Group's Shiller PE Ratio falls into.
For Shiller PE Ratio, the earnings of the past 10 years are inflation-adjusted and averaged. The result is used for P/E calculation. Since it looks at the average over the last 10 years, the Shiller PE Ratio is also called PE10.
The Shiller PE Ratio was first used by professor Robert Shiller to measure the valuation of the overall market. The same calculation is applied here to individual companies.
CoStar Group's Shiller PE Ratio for today is calculated as
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
CoStar Group's E10 for the quarter that ended in Jun. 2026 is calculated as:
For example, CoStar Group's adjusted earnings per share data for the three months ended in Jun. 2026 was:
Add all the adjusted EPS together and divide 10 will get our E10.
Please note that we use the CPI data of the country/region where the company is headquartered. If the CPI data for that country/region is not available, then we will use the CPI data of the United States as default.
CoStar Group (MIL:1CSGP) has a Shiller PE Ratio of 40.55 as of Aug. 15, 2026. Shiller price-earnings ratio is the ratio of share price to a company's inflation-adjusted earnings over a 10-year period. View historical data on CoStar Group and its competitors. This is 80% below median its historical median of 200.06. Over the past decade, CoStar Group's Shiller PE Ratio has ranged from 39.51 to 295.83. According to the industry distribution chart, CoStar Group ranks #915 out of 1036 companies in the Real Estate industry, placing it in the top 88.3%.
Is CoStar Group's Shiller PE Ratio too high?
CoStar Group's current Shiller PE Ratio of 40.55 is 80% below median its 10-year median of 200.06. Over the past 10 years, this metric has ranged from a low of 39.51 to a high of 295.83. The Real Estate industry median Shiller PE Ratio is 11.61. CoStar Group's value of 40.55 is 249.4% above this industry median. Based on the distribution chart, CoStar Group ranks #915 out of 1036 companies in the Real Estate industry, which is in the bottom quartile relative to peers. Overall, CoStar Group has a GF Score™ of 57/100 and is considered Significantly Undervalued, reflecting its overall financial health beyond just this single metric.
How does CoStar Group's Shiller PE Ratio compare to COMP and JLL?
According to the Real Estate industry distribution chart, CoStar Group ranks #915 out of 1036 companies for Shiller PE Ratio. This places CoStar Group in the lower half of its industry. The industry median Shiller PE Ratio is 11.61. CoStar Group's value of 40.55 is 249.4% above this benchmark. Historically, CoStar Group's own Shiller PE Ratio has ranged from 39.51 to 295.83 over the past decade. While the company's 10-year median is 200.06 vs. the industry median of 11.61, CoStar Group has consistently been above the industry average. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Shiller PE Ratio for a Real Estate company?
The median Shiller PE Ratio among Real Estate companies is 11.61, based on 1,036 companies in the industry. Companies in the top quartile (top 25%) have a Shiller PE Ratio significantly above this median, while those in the bottom quartile fall well below. However, Shiller PE Ratio should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. CoStar Group's current Shiller PE Ratio of 40.55 is 249.4% above the industry median. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Shiller PE Ratio mean?
A high Shiller PE Ratio can signal that a stock is expensive relative to its fundamentals. Shiller price-earnings ratio is the ratio of share price to a company's inflation-adjusted earnings over a 10-year period. View historical data on CoStar Group and its competitors. For the Real Estate industry, the median Shiller PE Ratio is 11.61 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. CoStar Group's current Shiller PE Ratio is 40.55, which is 80% below median its own 10-year median of 200.06. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is CoStar Group stock overvalued right now?
Based on GuruFocus' analysis, CoStar Group (MIL:1CSGP) is currently considered Significantly Undervalued. The stock's GF Value™ is €85.00, compared to a current price of €26.76 — trading 68.5% below its estimated fair value. The current Shiller PE Ratio is 40.55, which is 80% below median its 10-year median of 200.06 and 249.4% above the Real Estate industry median of 11.61. CoStar Group's overall GF Score™ is 57/100 with 2 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Shiller PE Ratio calculated?
Shiller PE Ratio is calculated from a company's financial statements. For CoStar Group (MIL:1CSGP), the current Shiller PE Ratio is 40.55 as of Aug. 15, 2026. GuruFocus calculates this using data sourced from SEC filings and annual reports. See the calculation section and 30-year financial data on this page for the full breakdown.
Is CoStar Group (MIL:1CSGP) Overvalued in 2026?
Based on GuruFocus' analysis, CoStar Group stock appears to be undervalued.
The current stock price of €26.76 is trading 68.5% below its estimated GF Value™ of €85.00.
GuruFocus considers CoStar Group to be Significantly Undervalued.
Key valuation signals for MIL:1CSGP:
Shiller PE Ratio: 40.55 (80% below median its 10-year median of 200.06)
GF Value™: €85.00 vs. price of €26.76 (68.5% below fair value)
Industry Position: 249.4% above the Real Estate median (#915 of 1036)
No single metric tells the full story. See the MIL:1CSGP stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
CoStar Group is a global provider of proprietary information, analytics, and online marketplaces serving both commercial and residential real estate. The firm operates through a diverse portfolio of brands, including CoStar Suite for commercial real estate research, LoopNet for commercial listings, Apartments.com for multifamily rentals, and Homes.com for residential brokerage. It primarily sells high-margin software-as-a-service subscriptions that provide institutional clients with forensic property data and premium advertising visibility. With operations across North America, Europe, and Asia-Pacific, CoStar maintains the industry's most comprehensive centralized real estate database, functioning as a critical information utility for brokers, lenders, and owners worldwide.
57GF Score
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