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Quest DiagnosticsMEX:DGX 70 Cyclically Adjusted PB Ratio is 4.24 as of Sep. 06, 2026, which is 28% above its 10-year median of 3.31. GuruFocus rates MEX:DGX with a GF Score™ of 70/100 and a GF Value™ of MXN3,149.98 (Modestly Overvalued). The stock has 7 warning signs investors should review. Among 127 Medical Diagnostics & Research companies, Quest Diagnostics ranks worse than 77.95% on this metric.
The historical rank and industry rank for Quest Diagnostics's Cyclically Adjusted PB Ratio or its related term are showing as below:
MEX:DGX'
s Cyclically Adjusted PB Ratio Range Over the Past 10 Years
Min: 2.2 Med: 3.31 Max: 4.41
Current: 4.06
During the past years, Quest Diagnostics's highest Cyclically Adjusted PB Ratio was 4.41. The lowest was 2.20. And the median was 3.31.
MEX:DGX's Cyclically Adjusted PB Ratio is ranked worse than 77.95% of 127
companies
in the Medical Diagnostics & Research industry
Industry Median: 1.82
vs MEX:DGX: 4.06
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.
Quest Diagnostics's adjusted book value per share data for the three months ended in Jun. 2026 was MXN1,192.243. 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 MXN956.60 for the trailing ten years ended in Jun. 2026.
Shiller PE for Stocks: The True Measure of Stock Valuation
Quest Diagnostics (MEX:DGX) 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.
Quest Diagnostics Cyclically Adjusted PB Ratio Related Terms
Quest Diagnostics Cyclically Adjusted PB Ratio Historical Data
* Premium members only.
The historical data trend for Quest Diagnostics'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.
Quest Diagnostics Cyclically Adjusted PB Ratio Chart
MEX:DGX vs LH, MTD, GH: Cyclically Adjusted PB Ratio Comparison
For the Diagnostics & Research subindustry, Quest Diagnostics'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.
Quest Diagnostics Cyclically Adjusted PB Ratio vs Medical Diagnostics & Research Industry
For the Medical Diagnostics & Research industry and Healthcare sector, Quest Diagnostics's Cyclically Adjusted PB Ratio distribution charts can be found below:
* The bar in red indicates where Quest Diagnostics's Cyclically Adjusted PB Ratio falls into.
Quest Diagnostics 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.
Quest Diagnostics'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 4.24 mean?
Quest Diagnostics (MEX:DGX) has a Cyclically Adjusted PB Ratio of 4.24 as of Sep. 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 Quest Diagnostics and its competitors. This is 28% above median its historical median of 3.31. Over the past decade, Quest Diagnostics' Cyclically Adjusted PB Ratio has ranged from 2.20 to 4.41. According to the industry distribution chart, Quest Diagnostics ranks #99 out of 127 companies in the Medical Diagnostics & Research industry, placing it in the top 78%.
Is Quest Diagnostics' Cyclically Adjusted PB Ratio too high?
Quest Diagnostics' current Cyclically Adjusted PB Ratio of 4.24 is 28% above median its 10-year median of 3.31. Over the past 10 years, this metric has ranged from a low of 2.20 to a high of 4.41. The Medical Diagnostics & Research industry median Cyclically Adjusted PB Ratio is 1.82. Quest Diagnostics' value of 4.24 is 133% above this industry median. Based on the distribution chart, Quest Diagnostics ranks #99 out of 127 companies in the Medical Diagnostics & Research industry, which is in the bottom quartile relative to peers. Overall, Quest Diagnostics has a GF Score™ of 70/100 and is considered Modestly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Quest Diagnostics' Cyclically Adjusted PB Ratio compare to LH and MTD?
According to the Medical Diagnostics & Research industry distribution chart, Quest Diagnostics ranks #99 out of 127 companies for Cyclically Adjusted PB Ratio. This places Quest Diagnostics in the lower half of its industry. The industry median Cyclically Adjusted PB Ratio is 1.82. Quest Diagnostics' value of 4.24 is 133% above this benchmark. Historically, Quest Diagnostics' own Cyclically Adjusted PB Ratio has ranged from 2.20 to 4.41 over the past decade. While the company's 10-year median is 3.31 vs. the industry median of 1.82, Quest Diagnostics 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 Medical Diagnostics & Research company?
The median Cyclically Adjusted PB Ratio among Medical Diagnostics & Research companies is 1.82, based on 127 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. Quest Diagnostics's current Cyclically Adjusted PB Ratio of 4.24 is 133% 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 Quest Diagnostics and its competitors. For the Medical Diagnostics & Research industry, the median Cyclically Adjusted PB Ratio is 1.82 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Quest Diagnostics's current Cyclically Adjusted PB Ratio is 4.24, which is 28% above median its own 10-year median of 3.31. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Quest Diagnostics stock overvalued right now?
Based on GuruFocus' analysis, Quest Diagnostics (MEX:DGX) is currently considered Modestly Overvalued. The stock's GF Value™ is MXN3,149.98, compared to a current price of MXN4,051.76 — trading 28.6% above its estimated fair value. The current Cyclically Adjusted PB Ratio is 4.24, which is 28% above median its 10-year median of 3.31 and 133% above the Medical Diagnostics & Research industry median of 1.82. Quest Diagnostics' overall GF Score™ is 70/100 with 7 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 Quest Diagnostics (MEX:DGX), the current Cyclically Adjusted PB Ratio is 4.24 as of Sep. 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 Quest Diagnostics (MEX:DGX) Overvalued in 2026?
Based on GuruFocus' analysis, Quest Diagnostics stock appears to be overvalued.
The current stock price of MXN4,051.76 is trading 28.6% above its estimated GF Value™ of MXN3,149.98.
GuruFocus considers Quest Diagnostics to be Modestly Overvalued.
Key valuation signals for MEX:DGX:
Cyclically Adjusted PB Ratio: 4.24 (28% above median its 10-year median of 3.31)
GF Value™: MXN3,149.98 vs. price of MXN4,051.76 (28.6% above fair value)
Industry Position: 133% above the Medical Diagnostics & Research median (#99 of 127)
No single metric tells the full story. See the MEX:DGX stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Quest Diagnostics is a leading independent provider of diagnostic testing, information, and services in the US. The company generates over 97% of its revenue through clinical testing, anatomic pathology, esoteric testing, and substance abuse testing with specimens collected at its national network of roughly 2,400 patient service centers, as well as multiple doctors offices and hospitals. The firm also runs a much smaller diagnostic solutions segment that provides clinical trials testing, risk-assessment services, and information technology solutions.
70GF Score
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