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Century Aluminum CoSTU:EY3 +0.12%66 Piotroski F-Score is 7 as of Jul. 25, 2026, which is 75% above its 10-year median of 4.00. GuruFocus rates STU:EY3 with a GF Score™ of 66/100 and a GF Value™ of €19.23 (Significantly Overvalued). The stock has 6 warning signs investors should review. Among 2,502 Metals & Mining companies, Century Aluminum Co ranks better than 95.52% on this metric.
Good Sign:
Piotroski F-Score is 7, indicates a very healthy situation.
The zones of discrimination were as such:
Good or high score = 7, 8, 9
Bad or low score = 0, 1, 2, 3
Century Aluminum Co has an F-score of 6 indicating the company's financial situation is typical for a stable company.
The historical rank and industry rank for Century Aluminum Co's Piotroski F-Score or its related term are showing as below:
STU:EY3'
s Piotroski F-Score Range Over the Past 10 Years
Min: 1 Med: 4 Max: 7
Current: 7
During the past 13 years, the highest Piotroski F-Score of Century Aluminum Co was 7. The lowest was 1. And the median was 4.
Century Aluminum Co (STU:EY3) Piotroski F-Score Explanation
The developer of the system is Joseph D. Piotroski is relatively unknown accounting professor who shuns publicity and rarely gives interviews.
He graduated from the University of Illinois with a B.S. in accounting in 1989, received an M.B.A. from Indiana University in 1994. Five years later, in 1999, after earning a Ph.D. in accounting from the University of Michigan, he became an associate professor of accounting at the University of Chicago.
He wanted to see if he can develop a system (using a simple nine-point scoring system) that can increase the returns of a strategy of investing in low price to book (referred to in the paper as high book to market) value companies.
What he found was something that exceeded his most optimistic expectations.
Buying only those companies that scored highest (8 or 9) on his nine-point scale, or F-Score as he called it, over the 20 year period from 1976 to 1996 led to an average out-performance over the market of 13.4%.
Even more impressive were the results of a strategy of investing in the highest F-Score companies (8 or 9) and shorting companies with the lowest F-Score (0 or 1).
Over the same period from 1976 to 1996 (20 years) this strategy led to an average yearly return of 23%, substantially outperforming the average S&P 500 index return of 15.83% over the same period.
Century Aluminum Co Piotroski F-Score Related Terms
Century Aluminum Co Piotroski F-Score Historical Data
* Premium members only.
The historical data trend for Century Aluminum Co's Piotroski F-Score 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.
STU:EY3 vs CSTM, KALU, AA: Piotroski F-Score Comparison
For the Aluminum subindustry, Century Aluminum Co's Piotroski F-Score, along with its competitors' market caps and Piotroski F-Score 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.
Century Aluminum Co Piotroski F-Score vs Metals & Mining Industry
For the Metals & Mining industry and Basic Materials sector, Century Aluminum Co's Piotroski F-Score distribution charts can be found below:
* The bar in red indicates where Century Aluminum Co's Piotroski F-Score falls into.
* 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: If the latest quarterly/semi-annual/annual total assets data is 0, then we will use previous quarterly/semi-annual/annual data for all the items in the balance sheet.
Profitability
Question 1. Return on Assets (ROA)
Net income before extraordinary items for the year divided by Total Assets at the beginning of the year.
Score 1 if positive, 0 if negative.
Century Aluminum Co's current Net Income (TTM) was 302.
==> Positive ==> Score 1.
Question 2. Cash Flow Return on Assets (CFROA)
Net cash flow from operating activities (operating cash flow) divided by Total Assets at the beginning of the year.
Century Aluminum Co's return on assets of this year was 0.16714364. Century Aluminum Co's return on assets of last year was 0.06518096.
==> This year is higher. ==> Score 1.
Question 4. Quality of Earnings (Accrual)
Compare Cash flow return on assets (2) to return on assets (1)
Century Aluminum Co's gearing of this year was 0.21728018. Century Aluminum Co's gearing of last year was 0.23553852.
==> This year is lower or equal to last year. ==> Score 1.
Question 6. Change in Working Capital (Liquidity)
Compare this year's current ratio (current assets divided by current liabilities) to last year's current ratio.
Score 1 if this year's current ratio is higher, 0 if it's lower
Century Aluminum Co's current ratio of this year was 2.30310401. Century Aluminum Co's current ratio of last year was 1.83705735.
==> This year's current ratio is higher. ==> Score 1.
Question 7. Change in Shares in Issue
Compare the number of shares in issue this year, to the number in issue last year.
Score 0 if there is larger number of shares in issue this year, 1 otherwise.
Century Aluminum Co's number of shares in issue this year was 104.6. Century Aluminum Co's number of shares in issue last year was 99.2.
==> There is larger number of shares in issue this year. ==> Score 0.
Efficiency
Question 8. Change in Gross Margin
Compare this year's gross margin (Gross Profit divided by sales) to last year's.
Score 1 if this year's gross margin is higher, 0 if it's lower.
Century Aluminum Co's gross margin of this year was 0.12365006. Century Aluminum Co's gross margin of last year was 0.08952445.
==> This year's gross margin is higher. ==> Score 1.
Question 9. Change in asset turnover
Compare this year's asset turnover (total sales for the year divided by total assets at the beginning of the year) to last year's asset turnover ratio.
Score 1 if this year's asset turnover ratio is higher, 0 if it's lower
Century Aluminum Co's asset turnover of this year was 1.20909369. Century Aluminum Co's asset turnover of last year was 1.29006915.
==> Last year's asset turnover is higher ==> Score 0.
Evaluation
Piotroski F-Score
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Good or high score = 7, 8, 9
Bad or low score = 0, 1, 2, 3
Century Aluminum Co has an F-score of 6 indicating the company's financial situation is typical for a stable company.
Century Aluminum Co (STU:EY3) has a Piotroski F-Score of 7 as of Jul. 25, 2026. The Piotroski F-score grades a company's business operating strength from 0-9. View historical data on Century Aluminum Co and its competitors. This is 75% above median its historical median of 4.00. Over the past decade, Century Aluminum Co's Piotroski F-Score has ranged from 1.00 to 7.00. According to the industry distribution chart, Century Aluminum Co ranks #112 out of 2502 companies in the Metals & Mining industry, placing it in the top 4.5%.
Is Century Aluminum Co's Piotroski F-Score too high?
Century Aluminum Co's current Piotroski F-Score of 7 is 75% above median its 10-year median of 4.00. Over the past 10 years, this metric has ranged from a low of 1.00 to a high of 7.00. The Metals & Mining industry median Piotroski F-Score is 3.00. Century Aluminum Co's value of 7 is 133.3% above this industry median. Based on the distribution chart, Century Aluminum Co ranks #112 out of 2502 companies in the Metals & Mining industry, which is in the top quartile — a strong position relative to peers. Overall, Century Aluminum Co has a GF Score™ of 66/100 and is considered Significantly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Century Aluminum Co's Piotroski F-Score compare to CSTM and KALU?
According to the Metals & Mining industry distribution chart, Century Aluminum Co ranks #112 out of 2502 companies for Piotroski F-Score. This places Century Aluminum Co in the top 5% of its industry — outperforming the majority of peers. The industry median Piotroski F-Score is 3.00. Century Aluminum Co's value of 7 is 133.3% above this benchmark. Historically, Century Aluminum Co's own Piotroski F-Score has ranged from 1.00 to 7.00 over the past decade. While the company's 10-year median is 4.00 vs. the industry median of 3.00, Century Aluminum Co 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 Piotroski F-Score for a Metals & Mining company?
The median Piotroski F-Score among Metals & Mining companies is 3.00, based on 2,502 companies in the industry. Companies in the top quartile (top 25%) have a Piotroski F-Score significantly above this median, while those in the bottom quartile fall well below. However, Piotroski F-Score should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Century Aluminum Co's current Piotroski F-Score of 7 is 133.3% 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 Piotroski F-Score mean?
A high Piotroski F-Score can signal that a stock is expensive relative to its fundamentals. The Piotroski F-score grades a company's business operating strength from 0-9. View historical data on Century Aluminum Co and its competitors. For the Metals & Mining industry, the median Piotroski F-Score is 3.00 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Century Aluminum Co's current Piotroski F-Score is 7, which is 75% above median its own 10-year median of 4.00. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Century Aluminum Co stock overvalued right now?
Based on GuruFocus' analysis, Century Aluminum Co (STU:EY3) is currently considered Significantly Overvalued. The stock's GF Value™ is €19.23, compared to a current price of €40.50 — trading 110.6% above its estimated fair value. The current Piotroski F-Score is 7, which is 75% above median its 10-year median of 4.00 and 133.3% above the Metals & Mining industry median of 3.00. Century Aluminum Co's overall GF Score™ is 66/100 with 6 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Piotroski F-Score calculated?
Piotroski F-Score is calculated from a company's financial statements. For Century Aluminum Co (STU:EY3), the current Piotroski F-Score is 7 as of Jul. 25, 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 Century Aluminum Co (STU:EY3) Overvalued in 2026?
Based on GuruFocus' analysis, Century Aluminum Co stock appears to be overvalued.
The current stock price of €40.50 is trading 110.6% above its estimated GF Value™ of €19.23.
GuruFocus considers Century Aluminum Co to be Significantly Overvalued.
Key valuation signals for STU:EY3:
Piotroski F-Score: 7 (75% above median its 10-year median of 4.00)
GF Value™: €19.23 vs. price of €40.50 (110.6% above fair value)
Industry Position: 133.3% above the Metals & Mining median (#112 of 2502)
No single metric tells the full story. See the STU:EY3 stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Century Aluminum Co produces primary aluminum standard grade and value-added products. The firm operates smelter facilities in the United States and Iceland. The majority of revenue is generated from Glencore, which agreed to purchase nearly all of Century Aluminum's North American production. The company produces high purity aluminum, standard-grade aluminum sow and tee bars, and value-added billet and foundry products. The company also owns a carbon anode production facility in the Netherlands.
66GF Score
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