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American TowerMIL:1AMT 54 Cyclically Adjusted PB Ratio is 12.32 as of Jul. 18, 2026, which is 11% below its 10-year median of 13.86. GuruFocus rates MIL:1AMT with a GF Score™ of 54/100 and a GF Value™ of €178.30 (Modestly Undervalued). The stock has 5 warning signs investors should review. Among 558 REITs companies, American Tower ranks worse than 98.92% on this metric.
The historical rank and industry rank for American Tower's Cyclically Adjusted PB Ratio or its related term are showing as below:
MIL:1AMT'
s Cyclically Adjusted PB Ratio Range Over the Past 10 Years
Min: 9.59 Med: 13.86 Max: 22.83
Current: 12.37
During the past years, American Tower's highest Cyclically Adjusted PB Ratio was 22.83. The lowest was 9.59. And the median was 13.86.
MIL:1AMT's Cyclically Adjusted PB Ratio is ranked worse than 98.92% of 558
companies
in the REITs industry
Industry Median: 0.83
vs MIL:1AMT: 12.37
The Shiller PE Ratio was first used by professor Robert Shiller. He uses E10 for his Shiller PE Ratio calculation. E10 is the average of the inflation adjusted earnings per share of a company over the past 10 years. The similar calculation is applied by GuruFocus to calculate the Cyclically Adjusted PB Ratio. The Cyclically Adjusted Book per Share is the average of the inflation adjusted book value per share of a company over the past 10 years.
American Tower's adjusted book value per share data for the three months ended in Mar. 2026 was €6.539. Add all the adjusted book value per share for the past 10 years together and divide the count will get our Cyclically Adjusted Book per Share, which is €11.86 for the trailing ten years ended in Mar. 2026.
Shiller PE for Stocks: The True Measure of Stock Valuation
American Tower (MIL:1AMT) Cyclically Adjusted PB Ratio Explanation
Compared with the regular PB Ratio, which works poorly for cyclical businesses, the Cyclically Adjusted PB Ratio smoothed out the fluctuations of book value during business cycles. Therefore it is more accurate in reflecting the valuation of the company.
If a company has consistent business performance, the Cyclically Adjusted PB Ratio should give similar results to regular PB Ratio.
American Tower Cyclically Adjusted PB Ratio Related Terms
American Tower Cyclically Adjusted PB Ratio Historical Data
* Premium members only.
The historical data trend for American Tower's Cyclically Adjusted PB 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:1AMT vs DLR, EQIX, IRM: Cyclically Adjusted PB Ratio Comparison
For the REIT - Specialty subindustry, American Tower's Cyclically Adjusted PB Ratio, along with its competitors' market caps and Cyclically Adjusted PB 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.
American Tower Cyclically Adjusted PB Ratio vs REITs Industry
For the REITs industry and Real Estate sector, American Tower's Cyclically Adjusted PB Ratio distribution charts can be found below:
* The bar in red indicates where American Tower's Cyclically Adjusted PB Ratio falls into.
American Tower Cyclically Adjusted PB Ratio Calculation
Like the Shiller PE Ratio, the Cyclically Adjusted PB Ratio takes the Book Value per Share from the past 10 years, adjusts it for inflation, and then calculates the average. This average is then used for the P/B calculation. Because it considers this 10-year average, it's often referred to as the CAPB Ratio.
The Shiller PE Ratio was first used by professor Robert Shiller to measure the valuation of the overall market. The similar calculation is applied by GuruFocus to calculate the Cyclically Adjusted PB Ratio.
American Tower's Cyclically Adjusted PB 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.
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.
What does a Cyclically Adjusted PB Ratio of 12.32 mean?
American Tower (MIL:1AMT) has a Cyclically Adjusted PB Ratio of 12.32 as of Jul. 18, 2026. Cyclically Adjusted PB Ratio is the ratio of share price to a company's inflation-adjusted book value per share over a 10-year period. View historical data on American Tower and its competitors. This is 11% below median its historical median of 13.86. Over the past decade, American Tower's Cyclically Adjusted PB Ratio has ranged from 9.59 to 22.83. According to the industry distribution chart, American Tower ranks #552 out of 558 companies in the REITs industry, placing it in the top 98.9%.
Is American Tower's Cyclically Adjusted PB Ratio too high?
American Tower's current Cyclically Adjusted PB Ratio of 12.32 is 11% below median its 10-year median of 13.86. Over the past 10 years, this metric has ranged from a low of 9.59 to a high of 22.83. The REITs industry median Cyclically Adjusted PB Ratio is 0.83. American Tower's value of 12.32 is 1384.3% above this industry median. Based on the distribution chart, American Tower ranks #552 out of 558 companies in the REITs industry, which is in the bottom quartile relative to peers. Overall, American Tower has a GF Score™ of 54/100 and is considered Modestly Undervalued, reflecting its overall financial health beyond just this single metric.
How does American Tower's Cyclically Adjusted PB Ratio compare to DLR and EQIX?
According to the REITs industry distribution chart, American Tower ranks #552 out of 558 companies for Cyclically Adjusted PB Ratio. This places American Tower in the lower half of its industry. The industry median Cyclically Adjusted PB Ratio is 0.83. American Tower's value of 12.32 is 1384.3% above this benchmark. Historically, American Tower's own Cyclically Adjusted PB Ratio has ranged from 9.59 to 22.83 over the past decade. While the company's 10-year median is 13.86 vs. the industry median of 0.83, American Tower 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 Cyclically Adjusted PB Ratio for a REITs company?
The median Cyclically Adjusted PB Ratio among REITs companies is 0.83, based on 558 companies in the industry. Companies in the top quartile (top 25%) have a Cyclically Adjusted PB Ratio significantly above this median, while those in the bottom quartile fall well below. However, Cyclically Adjusted PB Ratio should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. American Tower's current Cyclically Adjusted PB Ratio of 12.32 is 1384.3% 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 Cyclically Adjusted PB Ratio mean?
A high Cyclically Adjusted PB Ratio can signal that a stock is expensive relative to its fundamentals. Cyclically Adjusted PB Ratio is the ratio of share price to a company's inflation-adjusted book value per share over a 10-year period. View historical data on American Tower and its competitors. For the REITs industry, the median Cyclically Adjusted PB Ratio is 0.83 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. American Tower's current Cyclically Adjusted PB Ratio is 12.32, which is 11% below median its own 10-year median of 13.86. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is American Tower stock overvalued right now?
Based on GuruFocus' analysis, American Tower (MIL:1AMT) is currently considered Modestly Undervalued. The stock's GF Value™ is €178.30, compared to a current price of €146.15 — trading 18% below its estimated fair value. The current Cyclically Adjusted PB Ratio is 12.32, which is 11% below median its 10-year median of 13.86 and 1384.3% above the REITs industry median of 0.83. American Tower's overall GF Score™ is 54/100 with 5 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Cyclically Adjusted PB Ratio calculated?
Cyclically Adjusted PB Ratio is calculated from a company's financial statements. For American Tower (MIL:1AMT), the current Cyclically Adjusted PB Ratio is 12.32 as of Jul. 18, 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 American Tower (MIL:1AMT) Overvalued in 2026?
Based on GuruFocus' analysis, American Tower stock appears to be undervalued.
The current stock price of €146.15 is trading 18% below its estimated GF Value™ of €178.30.
GuruFocus considers American Tower to be Modestly Undervalued.
Key valuation signals for MIL:1AMT:
Cyclically Adjusted PB Ratio: 12.32 (11% below median its 10-year median of 13.86)
GF Value™: €178.30 vs. price of €146.15 (18% below fair value)
Industry Position: 1384.3% above the REITs median (#552 of 558)
No single metric tells the full story. See the MIL:1AMT stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
American Tower owns and operates about 150,000 wireless towers throughout the US, Asia, Latin America, Europe, and Africa. It also owns and/or operates 30 data centers in 11 US markets through its CoreSite segment. The company's customer base in the tower business is very concentrated, with most revenue in each market generated by the top three or four mobile carriers. The company operates 42,000 towers in the US, which accounted for about half of total revenue in 2025. Outside the US, American Tower operates about 47,000 towers in Latin America (dominated by Brazil), 33,000 towers in Europe, and 28,000 towers in Africa. American Tower operates as a REIT.
54GF Score
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