American Tower (MIL:1AMT) Cyclically Adjusted Book per Share: €11.86 (As of Mar. 2026)


MIL:1AMT American Tower Corp MIL:1AMT
54 GF Score
Price €145.05
GF Value €181.04
Valuation Modestly Undervalued
! 5 Warning Signs
View Full Analysis

What is American Tower Cyclically Adjusted Book per Share?

American Tower MIL:1AMT +1.15% 54 Cyclically Adjusted Book per Share is €11.86 as of Mar. 2026. GuruFocus rates MIL:1AMT with a GF Score™ of 54/100 and a GF Value™ of €181.04 (Modestly Undervalued). The stock has 5 warning signs investors should review.

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. The similar calculation is applied by GuruFocus to calculate the Cyclically Adjusted Book per Share and 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 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.

During the past 12 months, American Tower's average Cyclically Adjusted Book Growth Rate was -6.60% per year. During the past 3 years, the average Cyclically Adjusted Book Growth Rate was -1.90% per year. During the past 5 years, the average Cyclically Adjusted Book Growth Rate was 2.10% per year. During the past 10 years, the average Cyclically Adjusted Book Growth Rate was 3.80% per year. Please click Growth Rate Calculation Example (GuruFocus) to see how GuruFocus calculates Wal-Mart Stores Inc (WMT)'s revenue growth rate. You can apply the same method to get the Cyclically Adjusted Book Growth Rate using Cyclically Adjusted Book per Share data.

During the past 13 years, the highest 3-Year average Cyclically Adjusted Book Growth Rate of American Tower was 6.50% per year. The lowest was -7.20% per year. And the median was 3.10% per year.

As of today (2026-07-02), American Tower's current stock price is €145.05. American Tower's Cyclically Adjusted Book per Share for the quarter that ended in Mar. 2026 was €11.86. American Tower's Cyclically Adjusted PB Ratio of today is 12.23.

During the past 13 years, the highest Cyclically Adjusted PB Ratio of American Tower was 22.83. The lowest was 9.59. And the median was 13.86.


American Tower  (MIL:1AMT) Cyclically Adjusted Book per Share Explanation

If a company grows much fast than inflation, Cyclically Adjusted Book per Share may underestimate the company's equity. Cyclically Adjusted PB Ratio can seem to be too high even the actual PB Ratio is low.

For the Cyclically Adjusted PB Ratio, the book value of the past 10 years are inflation-adjusted and averaged. The result is used for P/B calculation. Since it looks at the average over the last 10 years, the Cyclically Adjusted PB Ratio is also called CAPB Ratio.

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 Cyclically Adjusted PB Ratio of today is calculated as

Cyclically Adjusted PB Ratio=Share Price/Cyclically Adjusted Book per Share
=145.05/11.86
=12.23

* 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.

During the past 13 years, the highest Cyclically Adjusted PB Ratio of American Tower was 22.83. The lowest was 9.59. And the median was 13.86.


Be Aware

Cyclically Adjusted PB Ratio works better for cyclical companies. It gives you a better idea on the company's real book value.


American Tower Cyclically Adjusted Book per Share Related Terms


American Tower Cyclically Adjusted Book per Share Historical Data

* Premium members only.

The historical data trend for American Tower's Cyclically Adjusted Book per Share 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.

American Tower Cyclically Adjusted Book per Share Chart

American Tower Annual Data
Trend Dec16 Dec17 Dec18 Dec19 Dec20 Dec21 Dec22 Dec23 Dec24 Dec25
Cyclically Adjusted Book per Share
Get a 7-Day Free Trial Premium Member Only Premium Member Only 0.00 0.00 13.63 14.27 11.80

American Tower Quarterly Data
Jun21 Sep21 Dec21 Mar22 Jun22 Sep22 Dec22 Mar23 Jun23 Sep23 Dec23 Mar24 Jun24 Sep24 Dec24 Mar25 Jun25 Sep25 Dec25 Mar26
Cyclically Adjusted Book per Share Get a 7-Day Free Trial Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only 13.42 12.39 12.35 11.80 11.86

MIL:1AMT vs DLR, EQIX, IRM: Cyclically Adjusted Book per Share 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.


MIL:1AMT
54GF Score
American Tower Corp MIL:1AMT
Cyclically Adjusted Book per Share is just one metric. See GF Score™, valuation, warning signs, and more.
View Full Analysis

American Tower Cyclically Adjusted Book per Share Calculation

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. The similar calculation is applied by GuruFocus to calculate the Cyclically Adjusted Book per Share and 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.

What is Cyclically Adjusted Book per Share? How do we calculate Cyclically Adjusted Book per Share?

Cyclically Adjusted Book per Share is the average of the inflation adjusted Book Value per Share of a company over the past 10 years. Let's use an example to explain.

If we want to calculate the Cyclically Adjusted Book per Share of Wal-Mart (WMT) for Dec. 31, 2010, we need to have the inflation data and the book value per share from 2001 through 2010.

We adjusted the 2001 book value per share data with the total inflation from 2001 through 2010 to the equivalent book value in 2010. If the total inflation from 2001 to 2010 is 40%, and Wal-Mart's book value is $1 a share in 2001, then the 2001's equivalent book value in 2010 is $1.4 a share. If Wal-Mart's book value is $1 again in 2002, and the total inflation from 2002 through 2010 is 35%, then the equivalent 2002 book value in 2010 is $1.35. So on and so forth, you get the equivalent book value per share of past 10 years. Then you add them together and divided the sum by the count to get Cyclically Adjusted Book per Share.

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.

For example, American Tower's adjusted Book Value per Share data for the three months ended in Mar. 2026 was:

Adj_Book= Book Value per Share /CPI of Mar. 2026 (Change)*Current CPI (Mar. 2026)
=6.539/330.2130*330.2130
=6.539

Current CPI (Mar. 2026) = 330.2130.

American Tower Quarterly Data

Book Value per Share CPI Adj_Book
201606 14.176 241.018 19.422
201609 14.041 241.428 19.205
201612 15.010 241.432 20.530
201703 15.031 243.801 20.359
201706 13.443 244.955 18.122
201709 12.740 246.819 17.045
201712 12.299 246.524 16.474
201803 11.633 249.554 15.393
201806 10.770 251.989 14.113
201809 10.403 252.439 13.608
201812 10.634 251.233 13.977
201903 10.707 254.202 13.909
201906 10.958 256.143 14.127
201909 10.745 256.759 13.819
201912 10.273 256.974 13.201
202003 7.419 258.115 9.491
202006 7.248 257.797 9.284
202009 7.133 260.280 9.050
202012 7.573 260.474 9.601
202103 7.334 264.877 9.143
202106 10.496 271.696 12.757
202109 10.100 274.310 12.158
202112 9.866 278.802 11.685
202203 10.672 287.504 12.257
202206 14.139 296.311 15.757
202209 13.627 296.808 15.161
202212 11.298 296.797 12.570
202303 10.836 301.836 11.855
202306 10.230 305.109 11.072
202309 9.112 307.789 9.776
202312 8.256 306.746 8.888
202403 7.975 312.332 8.432
202406 7.669 314.175 8.060
202409 7.022 315.301 7.354
202412 6.911 315.605 7.231
202503 6.985 319.799 7.212
202506 6.875 322.561 7.038
202509 7.191 324.800 7.311
202512 6.689 324.054 6.816
202603 6.539 330.213 6.539

Add all the adjusted book value per share together and divide the count will get our Cyclically Adjusted Book per Share.

What does a Cyclically Adjusted Book per Share of €11.86 mean?
American Tower (MIL:1AMT) has a Cyclically Adjusted Book per Share of €11.86 as of Mar. 2026. Cyclically adjusted book value per share represents the company's inflation-adjusted book value per share over a 10-year period. View historical data on American Tower and its competitors.
Is American Tower's Cyclically Adjusted Book per Share too high?
American Tower's current Cyclically Adjusted Book per Share is €11.86. 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 Book per Share compare to DLR and EQIX?
American Tower's Cyclically Adjusted Book per Share of €11.86 can be compared against companies in the REITs industry. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Cyclically Adjusted Book per Share for a REITs company?
A good Cyclically Adjusted Book per Share depends on the REITs industry context. However, Cyclically Adjusted Book per Share should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Cyclically Adjusted Book per Share mean?
A high Cyclically Adjusted Book per Share can signal that a stock is expensive relative to its fundamentals. Cyclically adjusted book value per share represents the company's inflation-adjusted book value per share over a 10-year period. View historical data on American Tower and its competitors. American Tower's current Cyclically Adjusted Book per Share is €11.86. 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 €181.04, compared to a current price of €145.05 — trading 19.9% below its estimated fair value. The current Cyclically Adjusted Book per Share is €11.86. 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 Book per Share calculated?
Cyclically Adjusted Book per Share is calculated from a company's financial statements. For American Tower (MIL:1AMT), the current Cyclically Adjusted Book per Share is €11.86 as of Mar. 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 €145.05 is trading 19.9% below its estimated GF Value™ of €181.04. GuruFocus considers American Tower to be Modestly Undervalued.

Key valuation signals for MIL:1AMT:

  • Cyclically Adjusted Book per Share: €11.86
  • GF Value™: €181.04 vs. price of €145.05 (19.9% below fair value)
  • GF Score™: 54/100 with 5 warning signs

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 Business Description

Industry Real EstateREITs
Address 222 Berkeley Street, 7th Floor, Boston, MA, USA, 02116
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

Get the complete analysis for MIL:1AMT

Cyclically Adjusted Book per Share is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.

€145.05
Price
€181.04
GF Value