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ROC % measures how well a company generates cash flow relative to the capital it has invested in its business. It is also called ROIC %. Quest Diagnostics's annualized return on capital (ROC %) for the quarter that ended in Mar. 2026 was 8.53%.
As of today (2026-07-21), Quest Diagnostics's WACC % is 5.14%. Quest Diagnostics's ROC % is 8.44% (calculated using TTM income statement data).
Quest Diagnostics generates higher returns on investment than it costs the company to raise the capital needed for that investment. It is earning excess returns. A firm that expects to continue generating positive excess returns on new investments in the future will see its value increase as growth increases.
Quest Diagnostics (MEX:DGX) ROC % Explanation
ROC % measures how well a company generates cash flow relative to the capital it has invested in its business. It is also called ROIC %. The reason book values of debt and equity are used is because the book values are the capital the company received when issuing the debt or receiving the equity investments.
There are four key components to this definition. The first is the use of operating income or EBIT rather than net income in the numerator. The second is the tax adjustment to this operating income or EBIT, computed as a hypothetical tax based on an effective or marginal tax rate. The third is the use of book values for invested capital, rather than market values. The final is the timing difference; the capital invested is from the end of the prior year whereas the operating income or EBIT is the current year's number.
Why is ROC % important?
Because it costs money to raise capital. A firm that generates higher returns on investment than it costs the company to raise the capital needed for that investment is earning excess returns. A firm that expects to continue generating positive excess returns on new investments in the future will see its value increase as growth increases, whereas a firm that earns returns that do not match up to its cost of capital will destroy value as it grows.
As of today, Quest Diagnostics's WACC % is 5.14%. Quest Diagnostics's ROC % is 8.44% (calculated using TTM income statement data).
Quest Diagnostics generates higher returns on investment than it costs the company to raise the capital needed for that investment. It is earning excess returns. A firm that expects to continue generating positive excess returns on new investments in the future will see its value increase as growth increases.
Be Aware
Like ROE % and ROA %, ROC % is calculated with only 12 months of data. Fluctuations in the company's earnings or business cycles can affect the ratio drastically. It is important to look at the ratio from a long term perspective.
Quest Diagnostics ROC % Related Terms
Quest Diagnostics ROC % Historical Data
* Premium members only.
The historical data trend for Quest Diagnostics's ROC % 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.
Note:
The Operating Income data used here is four times the quarterly (Mar. 2026) data.
The tax rate is limited to between 0% and 100%.
* 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 (MEX:DGX) has a ROC % of 8.53% as of Mar. 2026. Return on capital is the ratio of current-period net income to average two-period capital. View historical data on Quest Diagnostics and its competitors.
Is Quest Diagnostics' ROC % too high?
Quest Diagnostics' current ROC % is 8.53%. Overall, Quest Diagnostics has a GF Score™ of 71/100 and is considered Fairly Valued, reflecting its overall financial health beyond just this single metric.
How does Quest Diagnostics' ROC % compare to LH and MTD?
Quest Diagnostics' ROC % of 8.53% 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 ROC % for a Medical Diagnostics & Research company?
A good ROC % depends on the Medical Diagnostics & Research industry context. However, ROC % 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 ROC % mean?
A high ROC % can signal that a stock is expensive relative to its fundamentals. Return on capital is the ratio of current-period net income to average two-period capital. View historical data on Quest Diagnostics and its competitors. Quest Diagnostics's current ROC % is 8.53%. 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 Fairly Valued. The stock's GF Value™ is MXN3,288.23, compared to a current price of MXN3,624.00 — trading 10.2% above its estimated fair value. The current ROC % is 8.53%. Quest Diagnostics' overall GF Score™ is 71/100 with 8 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is ROC % calculated?
ROC % is calculated from a company's financial statements. For Quest Diagnostics (MEX:DGX), the current ROC % is 8.53% 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 Quest Diagnostics (MEX:DGX) Overvalued in 2026?
Based on GuruFocus' analysis, Quest Diagnostics stock appears to be overvalued.
The current stock price of MXN3,624.00 is trading 10.2% above its estimated GF Value™ of MXN3,288.23.
GuruFocus considers Quest Diagnostics to be Fairly Valued.
Key valuation signals for MEX:DGX:
ROC %: 8.53%
GF Value™: MXN3,288.23 vs. price of MXN3,624.00 (10.2% above fair value)
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.
71GF Score
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