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Shares Outstanding (EOP) are shares that have been authorized, issued, and purchased by investors and are held by them.
3-Year Share Buyback Ratio measures the average annual proportion of a company's outstanding shares repurchased over the past three years. It is calculated as the annualized percentage change in shares outstanding from three years ago to the current year. A positive ratio may indicate share buybacks over the period, while a zero or negative ratio may reflect no repurchases or potential share issuance. Amphastar Pharmaceuticals's current 3-Year Share Buyback Ratio was 1.70%.
The historical rank and industry rank for Amphastar Pharmaceuticals's 3-Year Share Buyback Ratio or its related term are showing as below:
AMPH'
s 3-Year Share Buyback Ratio Range Over the Past 10 Years
Min: -2.1 Med: -0.85 Max: 1.7
Current: 1.7
During the past 13 years, Amphastar Pharmaceuticals's highest 3-Year Share Buyback Ratio was 1.70%. The lowest was -2.10%. And the median was -0.85%.
AMPH's 3-Year Share Buyback Ratio is ranked better than 95.52% of 647
companies
in the Drug Manufacturers industry
Industry Median: -2
vs AMPH: 1.70
Amphastar Pharmaceuticals (NAS:AMPH) 3-Year Share Buyback Ratio Explanation
A negative number means the company might be issuing new shares. A positive number indicates that the company is buying back shares.
Be Aware
Investors usually like share buybacks. But as pointed by Warren Buffett, only if a company buys back shares at the prices below the stock's intrinsic value, it rewards remaining shareholders. If a company buys its overvalued stocks back, it destroys shareholder value.
Amphastar Pharmaceuticals 3-Year Share Buyback Ratio Related Terms
AMPH vs ESPR, NIKA, BIOA: 3-Year Share Buyback Ratio Comparison
For the Drug Manufacturers - Specialty & Generic subindustry, Amphastar Pharmaceuticals's 3-Year Share Buyback Ratio, along with its competitors' market caps and 3-Year Share Buyback 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 3-Year Share Buyback Ratio vs Drug Manufacturers Industry
For the Drug Manufacturers industry and Healthcare sector, Amphastar Pharmaceuticals's 3-Year Share Buyback Ratio distribution charts can be found below:
* The bar in red indicates where Amphastar Pharmaceuticals's 3-Year Share Buyback Ratio falls into.
Amphastar Pharmaceuticals 3-Year Share Buyback Ratio Calculation
This is the annualized percentage change in shares outstanding from three years ago to the current year. The annualized percentage change is calculated with expontential compound based on the latest four years of annual data on Shares Outstanding (EOP).
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 average dividends per share growth rate.
What does a 3-Year Share Buyback Ratio of 1.70 mean?
Amphastar Pharmaceuticals (AMPH) has a 3-Year Share Buyback Ratio of 1.70 as of Mar. 2026. The 3-Year Share Buyback Ratio measures the average annual proportion of a company's outstanding shares repurchased over the past three years. It is calculated as the annualized percentage change in shares outstanding from three years ago to the current year. View historical data for Amphastar Pharmaceuticals and its competitors. According to the industry distribution chart, Amphastar Pharmaceuticals ranks #29 out of 647 companies in the Drug Manufacturers industry, placing it in the top 4.5%.
Is Amphastar Pharmaceuticals' 3-Year Share Buyback Ratio too high?
Amphastar Pharmaceuticals' current 3-Year Share Buyback Ratio is 1.70. Based on the distribution chart, Amphastar Pharmaceuticals ranks #29 out of 647 companies in the Drug Manufacturers industry, which is in the top quartile — a strong position relative to peers. 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' 3-Year Share Buyback Ratio compare to ESPR and NIKA?
According to the Drug Manufacturers industry distribution chart, Amphastar Pharmaceuticals ranks #29 out of 647 companies for 3-Year Share Buyback Ratio. This places Amphastar Pharmaceuticals in the top 5% of its industry — outperforming the majority of peers. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good 3-Year Share Buyback Ratio for a Drug Manufacturers company?
A good 3-Year Share Buyback Ratio depends on the Drug Manufacturers industry context. However, 3-Year Share Buyback Ratio 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 3-Year Share Buyback Ratio mean?
A high 3-Year Share Buyback Ratio can signal that a stock is expensive relative to its fundamentals. The 3-Year Share Buyback Ratio measures the average annual proportion of a company's outstanding shares repurchased over the past three years. It is calculated as the annualized percentage change in shares outstanding from three years ago to the current year. View historical data for Amphastar Pharmaceuticals and its competitors. Amphastar Pharmaceuticals's current 3-Year Share Buyback Ratio is 1.70. 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 $49.12, compared to a current price of $20.21 — trading 58.9% below its estimated fair value. The current 3-Year Share Buyback Ratio is 1.70. Amphastar Pharmaceuticals' overall GF Score™ is 84/100 with 4 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is 3-Year Share Buyback Ratio calculated?
3-Year Share Buyback Ratio is calculated from a company's financial statements. For Amphastar Pharmaceuticals (AMPH), the current 3-Year Share Buyback Ratio is 1.70 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 Amphastar Pharmaceuticals (AMPH) Overvalued in 2026?
Based on GuruFocus' analysis, Amphastar Pharmaceuticals stock appears to be undervalued.
The current stock price of $20.21 is trading 58.9% below its estimated GF Value™ of $49.12.
GuruFocus considers Amphastar Pharmaceuticals to be Significantly Undervalued.
Key valuation signals for AMPH:
3-Year Share Buyback Ratio: 1.70
GF Value™: $49.12 vs. price of $20.21 (58.9% below fair value)
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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3-Year Share Buyback Ratio is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.
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