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Costain GroupCSGQF 52 Shiller PE Ratio is 15.28 as of Aug. 31, 2026, which is 109% above its 10-year median of 7.32. GuruFocus rates CSGQF with a GF Score™ of 52/100 and a GF Value™ of $0.58. The stock has 5 warning signs investors should review. Among 1,038 Construction companies, Costain Group ranks worse than 63.87% on this metric.
As of today (2026-08-31), Costain Group's current share price is $1.375. Costain Group's E10 for the fiscal year that ended in Dec25 was $0.09. Costain Group's Shiller PE Ratio for today is 15.28.
The historical rank and industry rank for Costain Group's Shiller PE Ratio or its related term are showing as below:
CSGQF'
s Shiller PE Ratio Range Over the Past 10 Years
Min: 1.3 Med: 7.32 Max: 29.18
Current: 23.2
During the past 13 years, Costain Group's highest Shiller PE Ratio was 29.18. The lowest was 1.30. And the median was 7.32.
CSGQF's Shiller PE Ratio is ranked worse than 63.87% of 1038
companies
in the Construction industry
Industry Median: 17.01
vs CSGQF: 23.20
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.
Costain Group's adjusted earnings per share data of for the fiscal year that ended in Dec25 was $0.183. Add all the adjusted EPS for the past 10 years together and divide 10 will get our E10, which is $0.09 for the trailing ten years ended in Dec25.
Shiller PE for Stocks: The True Measure of Stock Valuation
Costain Group (OTCPK:CSGQF) 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.
Costain Group Shiller PE Ratio Related Terms
Costain Group Shiller PE Ratio Historical Data
* Premium members only.
The historical data trend for Costain 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.
CSGQF vs PWR, FIX, EME: Shiller PE Ratio Comparison
For the Engineering & Construction subindustry, Costain 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.
Costain Group Shiller PE Ratio vs Construction Industry
For the Construction industry and Industrials sector, Costain Group's Shiller PE Ratio distribution charts can be found below:
* The bar in red indicates where Costain 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.
Costain 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.
Costain Group's E10 for the fiscal year that ended in Dec25 is calculated as:
For example, Costain Group's adjusted earnings per share data for the fiscal year that ended in Dec25 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.
Costain Group (CSGQF) has a Shiller PE Ratio of 15.28 as of Aug. 31, 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 Costain Group and its competitors. This is 109% above median its historical median of 7.32. Over the past decade, Costain Group's Shiller PE Ratio has ranged from 1.30 to 29.18. According to the industry distribution chart, Costain Group ranks #663 out of 1038 companies in the Construction industry, placing it in the top 63.9%.
Is Costain Group's Shiller PE Ratio too high?
Costain Group's current Shiller PE Ratio of 15.28 is 109% above median its 10-year median of 7.32. Over the past 10 years, this metric has ranged from a low of 1.30 to a high of 29.18. The Construction industry median Shiller PE Ratio is 17.01. Costain Group's value of 15.28 is 10.2% below this industry median. Based on the distribution chart, Costain Group ranks #663 out of 1038 companies in the Construction industry, which is below the industry midpoint. Overall, Costain Group has a GF Score™ of 52/100, reflecting its overall financial health beyond just this single metric.
How does Costain Group's Shiller PE Ratio compare to PWR and FIX?
According to the Construction industry distribution chart, Costain Group ranks #663 out of 1038 companies for Shiller PE Ratio. This places Costain Group in the lower half of its industry. The industry median Shiller PE Ratio is 17.01. Costain Group's value of 15.28 is 10.2% below this benchmark. Historically, Costain Group's own Shiller PE Ratio has ranged from 1.30 to 29.18 over the past decade. While the company's 10-year median is 7.32 vs. the industry median of 17.01, Costain Group has consistently been below 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 Construction company?
The median Shiller PE Ratio among Construction companies is 17.01, based on 1,038 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. Costain Group's current Shiller PE Ratio of 15.28 is 10.2% below 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 Costain Group and its competitors. For the Construction industry, the median Shiller PE Ratio is 17.01 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Costain Group's current Shiller PE Ratio is 15.28, which is 109% above median its own 10-year median of 7.32. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Costain Group stock overvalued right now?
Costain Group (CSGQF) has a current Shiller PE Ratio of 15.28. The stock's GF Value™ is $0.58, compared to a current price of $1.38 — trading 137.1% above its estimated fair value. The current Shiller PE Ratio is 15.28, which is 109% above median its 10-year median of 7.32 and 10.2% below the Construction industry median of 17.01. Costain Group's overall GF Score™ is 52/100 with 5 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 Costain Group (CSGQF), the current Shiller PE Ratio is 15.28 as of Aug. 31, 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 Costain Group (CSGQF) Overvalued in 2026?
Based on GuruFocus' analysis, Costain Group stock appears to be overvalued.
The current stock price of $1.38 is trading 137.1% above its estimated GF Value™ of $0.58.
Key valuation signals for CSGQF:
Shiller PE Ratio: 15.28 (109% above median its 10-year median of 7.32)
GF Value™: $0.58 vs. price of $1.38 (137.1% above fair value)
Industry Position: 10.2% below the Construction median (#663 of 1038)
No single metric tells the full story. See the CSGQF stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Costain Group PLC offers solutions and services. It provides engineering and technology solutions and advisory and development, design, management, project delivery, technology integration and asset optimization and support services to highways, nuclear, oil and gas, power, water sectors, rail. The company has two segments Transportation and Natural resources. The transportation segment covers highways, rail, and nuclear markets and the Natural resources segment comprises of water, power and oil and gas markets. Majority of revenue is from Transportation Segment.
52GF Score
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