Quest Diagnostics (STU:QDI) Cyclically Adjusted Book per Share: €50.95 (As of Jun. 2026)

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STU:QDI Quest Diagnostics Inc STU:QDI
78 GF Score
Price €203.10
GF Value €167.26
Valuation Modestly Overvalued
! 7 Warning Signs
View Full Analysis

What is Quest Diagnostics Cyclically Adjusted Book per Share?

Quest Diagnostics STU:QDI -0.05% 78 Cyclically Adjusted Book per Share is €50.95 as of Jun. 2026. GuruFocus rates STU:QDI with a GF Score™ of 78/100 and a GF Value™ of €167.26 (Modestly Overvalued). The stock has 7 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.

Quest Diagnostics's adjusted book value per share for the three months ended in Jun. 2026 was €59.472. 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 €50.95 for the trailing ten years ended in Jun. 2026.

During the past 12 months, Quest Diagnostics's average Cyclically Adjusted Book Growth Rate was 7.60% per year. During the past 3 years, the average Cyclically Adjusted Book Growth Rate was 7.50% per year. During the past 5 years, the average Cyclically Adjusted Book Growth Rate was 9.50% per year. During the past 10 years, the average Cyclically Adjusted Book Growth Rate was 9.10% 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 Quest Diagnostics was 13.80% per year. The lowest was 7.50% per year. And the median was 9.10% per year.

As of today (2026-08-01), Quest Diagnostics's current stock price is €203.10. Quest Diagnostics's Cyclically Adjusted Book per Share for the quarter that ended in Jun. 2026 was €50.95. Quest Diagnostics's Cyclically Adjusted PB Ratio of today is 3.99.

During the past 13 years, the highest Cyclically Adjusted PB Ratio of Quest Diagnostics was 4.41. The lowest was 2.20. And the median was 3.31.


Quest Diagnostics  (STU:QDI) 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.

Quest Diagnostics's Cyclically Adjusted PB Ratio of today is calculated as

Cyclically Adjusted PB Ratio=Share Price/Cyclically Adjusted Book per Share
=203.10/50.95
=3.99

* 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 Quest Diagnostics was 4.41. The lowest was 2.20. And the median was 3.31.


Be Aware

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


Quest Diagnostics Cyclically Adjusted Book per Share Related Terms


Quest Diagnostics Cyclically Adjusted Book per Share Historical Data

* Premium members only.

The historical data trend for Quest Diagnostics'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.

Quest Diagnostics Cyclically Adjusted Book per Share Chart

Quest Diagnostics 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 34.71 41.82 43.55 50.06 47.49

Quest Diagnostics Quarterly Data
Sep21 Dec21 Mar22 Jun22 Sep22 Dec22 Mar23 Jun23 Sep23 Dec23 Mar24 Jun24 Sep24 Dec24 Mar25 Jun25 Sep25 Dec25 Mar26 Jun26
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 45.84 46.44 47.49 49.31 50.95

STU:QDI vs LH, MTD, ILMN: Cyclically Adjusted Book per Share 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.


STU:QDI
78GF Score
Quest Diagnostics Inc STU:QDI
Cyclically Adjusted Book per Share is just one metric. See GF Score™, valuation, warning signs, and more.
View Full Analysis

Quest Diagnostics 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, Quest Diagnostics's adjusted Book Value per Share data for the three months ended in Jun. 2026 was:

Adj_Book= Book Value per Share /CPI of Jun. 2026 (Change)*Current CPI (Jun. 2026)
=59.472/333.9520*333.9520
=59.472

Current CPI (Jun. 2026) = 333.9520.

Quest Diagnostics Quarterly Data

Book Value per Share CPI Adj_Book
201609 29.890 241.428 41.345
201612 32.024 241.432 44.296
201703 31.599 243.801 43.283
201706 30.738 244.955 41.906
201709 29.575 246.819 40.016
201712 30.802 246.524 41.726
201803 29.995 249.554 40.139
201806 32.874 251.989 43.567
201809 33.505 252.439 44.324
201812 33.962 251.233 45.144
201903 34.938 254.202 45.899
201906 35.787 256.143 46.658
201909 37.699 256.759 49.033
201912 38.172 256.974 49.607
202003 38.206 258.115 49.431
202006 38.641 257.797 50.056
202009 40.249 260.280 51.641
202012 41.774 260.474 53.558
202103 43.250 264.877 54.529
202106 40.133 271.696 49.329
202109 44.172 274.310 53.776
202112 47.924 278.802 57.404
202203 49.490 287.504 57.485
202206 51.836 296.311 58.421
202209 55.240 296.808 62.153
202212 50.117 296.797 56.391
202303 50.508 301.836 55.882
202306 51.498 305.109 56.366
202309 53.752 307.789 58.321
202312 51.900 306.746 56.503
202403 53.310 312.332 57.000
202406 55.334 314.175 58.817
202409 54.621 315.301 57.852
202412 58.518 315.605 61.920
202503 57.237 319.799 59.770
202506 56.135 322.561 58.117
202509 55.799 324.800 57.371
202512 55.543 324.054 57.240
202603 57.402 330.213 58.052
202606 59.472 333.952 59.472

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 €50.95 mean?
Quest Diagnostics (STU:QDI) has a Cyclically Adjusted Book per Share of €50.95 as of Jun. 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 Quest Diagnostics and its competitors.
Is Quest Diagnostics' Cyclically Adjusted Book per Share too high?
Quest Diagnostics' current Cyclically Adjusted Book per Share is €50.95. Overall, Quest Diagnostics has a GF Score™ of 78/100 and is considered Modestly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Quest Diagnostics' Cyclically Adjusted Book per Share compare to LH and MTD?
Quest Diagnostics' Cyclically Adjusted Book per Share of €50.95 can be compared against companies in the Medical Diagnostics & Research 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 Medical Diagnostics & Research company?
A good Cyclically Adjusted Book per Share depends on the Medical Diagnostics & Research 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 Quest Diagnostics and its competitors. Quest Diagnostics's current Cyclically Adjusted Book per Share is €50.95. 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 (STU:QDI) is currently considered Modestly Overvalued. The stock's GF Value™ is €167.26, compared to a current price of €203.10 — trading 21.4% above its estimated fair value. The current Cyclically Adjusted Book per Share is €50.95. Quest Diagnostics' overall GF Score™ is 78/100 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 Book per Share calculated?
Cyclically Adjusted Book per Share is calculated from a company's financial statements. For Quest Diagnostics (STU:QDI), the current Cyclically Adjusted Book per Share is €50.95 as of Jun. 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 (STU:QDI) Overvalued in 2026?

Based on GuruFocus' analysis, Quest Diagnostics stock appears to be overvalued. The current stock price of €203.10 is trading 21.4% above its estimated GF Value™ of €167.26. GuruFocus considers Quest Diagnostics to be Modestly Overvalued.

Key valuation signals for STU:QDI:

  • Cyclically Adjusted Book per Share: €50.95
  • GF Value™: €167.26 vs. price of €203.10 (21.4% above fair value)
  • GF Score™: 78/100 with 7 warning signs

No single metric tells the full story. See the STU:QDI stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.


Quest Diagnostics Business Description

Address 500 Plaza Drive, Secaucus, NJ, USA, 07094
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.
78GF Score

Get the complete analysis for STU:QDI

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

€203.10
Price
€167.26
GF Value