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AonAON +0.93%90 Cyclically Adjusted PB Ratio is 17.79 as of Aug. 06, 2026, which is 50% above its 10-year median of 11.89. GuruFocus rates AON with a GF Score™ of 90/100 and a GF Value™ of $391.48 (Fairly Valued). The stock has 2 warning signs investors should review. Among 414 Insurance companies, Aon ranks worse than 99.03% on this metric.
As of today (2026-08-06), Aon's current share price is $359.97. Aon's Cyclically Adjusted Book per Share for the quarter that ended in Jun. 2026 was $20.24. Aon's Cyclically Adjusted PB Ratio for today is 17.79.
The historical rank and industry rank for Aon's Cyclically Adjusted PB Ratio or its related term are showing as below:
AON'
s Cyclically Adjusted PB Ratio Range Over the Past 10 Years
Min: 4.68 Med: 11.89 Max: 23.54
Current: 17.67
During the past years, Aon's highest Cyclically Adjusted PB Ratio was 23.54. The lowest was 4.68. And the median was 11.89.
AON's Cyclically Adjusted PB Ratio is ranked worse than 99.03% of 414
companies
in the Insurance industry
Industry Median: 1.405
vs AON: 17.67
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.
Aon's adjusted book value per share data for the three months ended in Jun. 2026 was $45.274. 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 $20.24 for the trailing ten years ended in Jun. 2026.
Shiller PE for Stocks: The True Measure of Stock Valuation
Aon (NYSE:AON) 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.
Aon Cyclically Adjusted PB Ratio Related Terms
Aon Cyclically Adjusted PB Ratio Historical Data
* Premium members only.
The historical data trend for Aon'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.
AON vs MRSH, AJG, WTW: Cyclically Adjusted PB Ratio Comparison
For the Insurance Brokers subindustry, Aon'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.
Aon Cyclically Adjusted PB Ratio vs Insurance Industry
For the Insurance industry and Financial Services sector, Aon's Cyclically Adjusted PB Ratio distribution charts can be found below:
* The bar in red indicates where Aon's Cyclically Adjusted PB Ratio falls into.
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.
Aon'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 17.79 mean?
Aon (AON) has a Cyclically Adjusted PB Ratio of 17.79 as of Aug. 06, 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 Aon and its competitors. This is 50% above median its historical median of 11.89. Over the past decade, Aon's Cyclically Adjusted PB Ratio has ranged from 4.68 to 23.54. According to the industry distribution chart, Aon ranks #410 out of 414 companies in the Insurance industry, placing it in the top 99%.
Is Aon's Cyclically Adjusted PB Ratio too high?
Aon's current Cyclically Adjusted PB Ratio of 17.79 is 50% above median its 10-year median of 11.89. Over the past 10 years, this metric has ranged from a low of 4.68 to a high of 23.54. The Insurance industry median Cyclically Adjusted PB Ratio is 1.41. Aon's value of 17.79 is 1166.2% above this industry median. Based on the distribution chart, Aon ranks #410 out of 414 companies in the Insurance industry, which is in the bottom quartile relative to peers. Overall, Aon has a GF Score™ of 90/100 and is considered Fairly Valued, reflecting its overall financial health beyond just this single metric.
How does Aon's Cyclically Adjusted PB Ratio compare to MRSH and AJG?
According to the Insurance industry distribution chart, Aon ranks #410 out of 414 companies for Cyclically Adjusted PB Ratio. This places Aon in the lower half of its industry. The industry median Cyclically Adjusted PB Ratio is 1.41. Aon's value of 17.79 is 1166.2% above this benchmark. Historically, Aon's own Cyclically Adjusted PB Ratio has ranged from 4.68 to 23.54 over the past decade. While the company's 10-year median is 11.89 vs. the industry median of 1.41, Aon 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 an Insurance company?
The median Cyclically Adjusted PB Ratio among Insurance companies is 1.41, based on 414 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. Aon's current Cyclically Adjusted PB Ratio of 17.79 is 1166.2% 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 Aon and its competitors. For the Insurance industry, the median Cyclically Adjusted PB Ratio is 1.41 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Aon's current Cyclically Adjusted PB Ratio is 17.79, which is 50% above median its own 10-year median of 11.89. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Aon stock overvalued right now?
Based on GuruFocus' analysis, Aon (AON) is currently considered Fairly Valued. The stock's GF Value™ is $391.48, compared to a current price of $359.97 — trading 8% below its estimated fair value. The current Cyclically Adjusted PB Ratio is 17.79, which is 50% above median its 10-year median of 11.89 and 1166.2% above the Insurance industry median of 1.41. Aon's overall GF Score™ is 90/100 with 2 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 Aon (AON), the current Cyclically Adjusted PB Ratio is 17.79 as of Aug. 06, 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 Aon (AON) Overvalued in 2026?
Based on GuruFocus' analysis, Aon stock appears to be undervalued.
The current stock price of $359.97 is trading 8% below its estimated GF Value™ of $391.48.
GuruFocus considers Aon to be Fairly Valued.
Key valuation signals for AON:
Cyclically Adjusted PB Ratio: 17.79 (50% above median its 10-year median of 11.89)
GF Value™: $391.48 vs. price of $359.97 (8% below fair value)
Industry Position: 1166.2% above the Insurance median (#410 of 414)
No single metric tells the full story. See the AON stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Aon is a leading global provider of insurance and reinsurance brokerage and human resources solutions. Its operations are tilted toward its brokerage operations. Headquartered in London, Aon has about 60,000 employees and operations in over 120 countries.
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