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Amphastar PharmaceuticalsAMPH +0.59%84 Shiller PE Ratio is 15.95 as of Aug. 29, 2026, which is 67% below its 10-year median of 48.83. GuruFocus rates AMPH with a GF Score™ of 84/100 and a GF Value™ of $35.90 (Significantly Undervalued). The stock has 5 warning signs investors should review. Among 528 Drug Manufacturers companies, Amphastar Pharmaceuticals ranks better than 71.59% on this metric.
The historical rank and industry rank for Amphastar Pharmaceuticals's Shiller PE Ratio or its related term are showing as below:
AMPH'
s Shiller PE Ratio Range Over the Past 10 Years
Min: 12.78 Med: 48.83 Max: 114.2
Current: 15.94
During the past years, Amphastar Pharmaceuticals's highest Shiller PE Ratio was 114.20. The lowest was 12.78. And the median was 48.83.
AMPH's Shiller PE Ratio is ranked better than 71.59% of 528
companies
in the Drug Manufacturers industry
Industry Median: 25.9
vs AMPH: 15.94
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.
Amphastar Pharmaceuticals's adjusted earnings per share data for the three months ended in Jun. 2026 was $0.670. Add all the adjusted EPS for the past 10 years together and divide 10 will get our E10, which is $1.38 for the trailing ten years ended in Jun. 2026.
Shiller PE for Stocks: The True Measure of Stock Valuation
Amphastar Pharmaceuticals (NAS:AMPH) Shiller PE Ratio Explanation
Compared with the regular PE Ratio, which works poorly for cyclical businesses, the Shiller PE Ratio smoothed out the fluctuations of profit margins during business cycles. Therefore it is more accurate in reflecting the valuation of the company.
If a company has consistent business performance, the Shiller PE Ratio should give similar results to regular PE Ratio.
Compared with the PS Ratio, the Shiller PE Ratio makes the comparison between different industries more meaningful.
Be Aware
Shiller PE Ratio assumes that over the long term, businesses and profitability revert to their means. If a company's business model does not work in the future compared with the past, Shiller PE Ratio and PS Ratio will give false valuations.
Amphastar Pharmaceuticals Shiller PE Ratio Related Terms
Amphastar Pharmaceuticals Shiller PE Ratio Historical Data
* 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.
AMPH vs ESPR, NIKA, BIOA: Shiller PE Ratio Comparison
For the Drug Manufacturers - Specialty & Generic subindustry, Amphastar Pharmaceuticals's Shiller PE Ratio, along with its competitors' market caps and Shiller PE 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.
Amphastar Pharmaceuticals Shiller PE Ratio vs Drug Manufacturers Industry
For the Drug Manufacturers industry and Healthcare sector, Amphastar Pharmaceuticals's Shiller PE Ratio distribution charts can be found below:
* The bar in red indicates where Amphastar Pharmaceuticals's Shiller PE Ratio falls into.
Amphastar Pharmaceuticals Shiller PE Ratio Calculation
For Shiller PE Ratio, the earnings of the past 10 years are inflation-adjusted and averaged. The result is used for P/E calculation. Since it looks at the average over the last 10 years, the Shiller PE Ratio is also called PE10.
The Shiller PE Ratio was first used by professor Robert Shiller to measure the valuation of the overall market. The same calculation is applied here to individual companies.
* 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.
Add all the adjusted EPS together and divide 10 will get our E10.
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.
Amphastar Pharmaceuticals (AMPH) has a Shiller PE Ratio of 15.95 as of Aug. 29, 2026. Shiller price-earnings ratio is the ratio of share price to a company's inflation-adjusted earnings over a 10-year period. View historical data on Amphastar Pharmaceuticals and its competitors. This is 67% below median its historical median of 48.83. Over the past decade, Amphastar Pharmaceuticals' Shiller PE Ratio has ranged from 12.78 to 114.20. According to the industry distribution chart, Amphastar Pharmaceuticals ranks #150 out of 528 companies in the Drug Manufacturers industry, placing it in the top 28.4%.
Is Amphastar Pharmaceuticals' Shiller PE Ratio too high?
Amphastar Pharmaceuticals' current Shiller PE Ratio of 15.95 is 67% below median its 10-year median of 48.83. Over the past 10 years, this metric has ranged from a low of 12.78 to a high of 114.20. The Drug Manufacturers industry median Shiller PE Ratio is 25.90. Amphastar Pharmaceuticals' value of 15.95 is 38.4% below this industry median. Based on the distribution chart, Amphastar Pharmaceuticals ranks #150 out of 528 companies in the Drug Manufacturers industry, which is above the industry midpoint. Overall, Amphastar Pharmaceuticals has a GF Score™ of 84/100 and is considered Significantly Undervalued, reflecting its overall financial health beyond just this single metric.
How does Amphastar Pharmaceuticals' Shiller PE Ratio compare to ESPR and NIKA?
According to the Drug Manufacturers industry distribution chart, Amphastar Pharmaceuticals ranks #150 out of 528 companies for Shiller PE Ratio. This puts Amphastar Pharmaceuticals in the upper half of its industry. The industry median Shiller PE Ratio is 25.90. Amphastar Pharmaceuticals' value of 15.95 is 38.4% below this benchmark. Historically, Amphastar Pharmaceuticals' own Shiller PE Ratio has ranged from 12.78 to 114.20 over the past decade. While the company's 10-year median is 48.83 vs. the industry median of 25.90, Amphastar Pharmaceuticals has consistently been below 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 Shiller PE Ratio for a Drug Manufacturers company?
The median Shiller PE Ratio among Drug Manufacturers companies is 25.90, based on 528 companies in the industry. Companies in the top quartile (top 25%) have a Shiller PE Ratio significantly above this median, while those in the bottom quartile fall well below. However, Shiller PE Ratio should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Amphastar Pharmaceuticals's current Shiller PE Ratio of 15.95 is 38.4% below 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 Shiller PE Ratio mean?
A high Shiller PE Ratio can signal that a stock is expensive relative to its fundamentals. Shiller price-earnings ratio is the ratio of share price to a company's inflation-adjusted earnings over a 10-year period. View historical data on Amphastar Pharmaceuticals and its competitors. For the Drug Manufacturers industry, the median Shiller PE Ratio is 25.90 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Amphastar Pharmaceuticals's current Shiller PE Ratio is 15.95, which is 67% below median its own 10-year median of 48.83. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Amphastar Pharmaceuticals stock overvalued right now?
Based on GuruFocus' analysis, Amphastar Pharmaceuticals (AMPH) is currently considered Significantly Undervalued. The stock's GF Value™ is $35.90, compared to a current price of $22.01 — trading 38.7% below its estimated fair value. The current Shiller PE Ratio is 15.95, which is 67% below median its 10-year median of 48.83 and 38.4% below the Drug Manufacturers industry median of 25.90. Amphastar Pharmaceuticals' overall GF Score™ is 84/100 with 5 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Shiller PE Ratio calculated?
Shiller PE Ratio is calculated from a company's financial statements. For Amphastar Pharmaceuticals (AMPH), the current Shiller PE Ratio is 15.95 as of Aug. 29, 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 Amphastar Pharmaceuticals (AMPH) Overvalued in 2026?
Based on GuruFocus' analysis, Amphastar Pharmaceuticals stock appears to be undervalued.
The current stock price of $22.01 is trading 38.7% below its estimated GF Value™ of $35.90.
GuruFocus considers Amphastar Pharmaceuticals to be Significantly Undervalued.
Key valuation signals for AMPH:
Shiller PE Ratio: 15.95 (67% below median its 10-year median of 48.83)
GF Value™: $35.90 vs. price of $22.01 (38.7% below fair value)
Industry Position: 38.4% below the Drug Manufacturers median (#150 of 528)
No single metric tells the full story. See the AMPH stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Amphastar Pharmaceuticals Inc is a bio-pharmaceutical company focusing on developing, manufacturing, marketing, and selling technically challenging generic and proprietary injectable, inhalation, and intranasal products, as well as insulin active pharmaceutical ingredient (or insulin API products. The company's finished products are used in hospital or urgent care clinical settings and are contracted and distributed through group purchasing organizations and drug wholesalers. The company has one reportable segment: pharmaceutical products. Geographically, the business presence of the firm is seen in the United States, China, and France, of which the U.S. accounts for the majority of the revenue.
84GF Score
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