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ACI WorldwideSTU:TSA -0.89%82 Peter Lynch Fair Value is €32.23 as of Aug. 20, 2026, which is 100% below its 10-year median of 1.72. GuruFocus rates STU:TSA with a GF Score™ of 82/100 and a GF Value™ of €43.79 (Fairly Valued). The stock has 2 warning signs investors should review. Among 661 Software companies, ACI Worldwide ranks worse than 57.34% on this metric.
Peter Lynch Fair Value applies to growing companies. The ideal range for the growth rate is between 10 - 20% a year. Peter Lynch thinks that the fair P/E value for a growth company equals its growth rate, that is PEG = 1. The earnings here is trailing twelve month (TTM) earnings. For non-bank companies, the growth rate we use is the average growth rate for EBITDA per share over the past 5 years. For Banks, the growth rate we use is the average growth rate for Book Value per share over the past 5 years. If 5-Year Growth Rate is greater than 25% a year, we use 25. If 5-Year Growth Rate is smaller than 5% a year, we do not calculate Peter Lynch Fair Value.
Here, as of today, ACI Worldwide's PEG is 1. ACI Worldwide's 5-Year TTM EBITDA Growth Rate is 11.96.
ACI Worldwide's EPS without NRI for the trailing twelve months (TTM) ended in Jun. 2026 was €2.70. Therefore, the Peter Lynch Fair Value for today is €32.23.
As of today (2026-08-20), ACI Worldwide's share price is €44.40. ACI Worldwide's Peter Lynch fair value is €32.23. Therefore, ACI Worldwide's Price to Peter Lynch Fair Value Ratio for today is 1.38.
The historical rank and industry rank for ACI Worldwide's Peter Lynch Fair Value or its related term are showing as below:
STU:TSA'
s Price-to-Peter-Lynch-Fair-Value Range Over the Past 10 Years
Min: 0.69 Med: 1.72 Max: 40.48
Current: 1.43
During the past 13 years, the highest Price to Peter Lynch Fair Value Ratio of ACI Worldwide was 40.48. The lowest was 0.69. And the median was 1.72.
STU:TSA's Price-to-Peter-Lynch-Fair-Value is ranked worse than 57.34% of 661
companies
in the Software industry
Industry Median: 1.26
vs STU:TSA: 1.43
Note: Please don't confuse Peter Lynch Fair Value with the value reached in Peter Lynch Chart.
ACI Worldwide (STU:TSA) Peter Lynch Fair Value Explanation
Peter Lynch Fair Value applies to growing companies. The ideal range for the growth rate is between 10 - 20% a year.
Peter Lynch thinks that the fair P/E value for a growth company equals its growth rate, that is PEG = 1. The earnings here is trailing twelve month (TTM) earnings. For non-bank companies, the growth rate we use is the average growth rate for EBITDA per share over the past 5 years. For Banks, the growth rate we use is the average growth rate for Book Value per share over the past 5 years.
Please don't confuse Peter Lynch Fair Value with the value reached in Peter Lynch Chart. In Peter Lynch chart, a fixed P/E ratio of 15 is used to draw the Earnings Line. Therefore the value reached has a P/E ratio of 15. But in Peter Lynch Fair Value calculation, P/E equals to the growth rate of EBITDA per share over the past 5 years, which is 11.96 instead of 15 in this case.
ACI Worldwide's Price to Peter Lynch Fair Value Ratio for today is calculated as
Price to Peter Lynch Fair Value
=
Share Price
/
Peter Lynch Fair Value
=
44.40
/
32.23
=
1.38
* 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.
ACI Worldwide Peter Lynch Fair Value Related Terms
ACI Worldwide Peter Lynch Fair Value Historical Data
* Premium members only.
The historical data trend for ACI Worldwide's Peter Lynch Fair Value 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:TSA vs PATH, DOX, WEX: Peter Lynch Fair Value Comparison
For the Software - Infrastructure subindustry, ACI Worldwide's Price-to-Peter-Lynch-Fair-Value, along with its competitors' market caps and Price-to-Peter-Lynch-Fair-Value 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.
ACI Worldwide Price-to-Peter-Lynch-Fair-Value vs Software Industry
For the Software industry and Technology sector, ACI Worldwide's Price-to-Peter-Lynch-Fair-Value distribution charts can be found below:
* The bar in red indicates where ACI Worldwide's Price-to-Peter-Lynch-Fair-Value falls into.
ACI Worldwide's EPS without NRI for the trailing twelve months (TTM) ended in Jun. 2026 adds up the quarterly data reported by the company within the most recent 12 months, which was €2.70.
* 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.
** Please be aware that the 5-Year TTM EBITDA Growth Rate is calculated based on TTM data over the last 5 years. For quarterly reported companies, the TTM data adds up the quarterly data reported by the company within the most recent 12 months. For companies that report semi-annually, annually, or do not have enough quarterly data, GuruFocus uses the annual data as the TTM data.
If 5-Year Earnings Growth Rate is greater than 25% a year, we use 25.
If 5-Year Earnings Growth Rate is smaller than 5% a year, we do not calculate Peter Lynch Fair Value.
Please note that we use the 5-year average growth rate of EBITDA per share as the growth rate for non-bank companies, as EBITDA growth is subject to less manipulations than net earnings per share. For banks, we use the 5-year average growth rate of Book Value per share as the growth rate. The reason is that EBITDA is not applicable to Banks and Book value is a relative important measurement for Banks. In the calculation, PEG=1 because Peter Lynch thinks that the fair P/E ratio of the growth stock is equal to its earnings growth rate.
What does a Peter Lynch Fair Value of €32.23 mean?
ACI Worldwide (STU:TSA) has a Peter Lynch Fair Value of €32.23 as of Aug. 20, 2026. Peter Lynch Fair Value is the stock value based on a company's current earnings and five-year earnings growth, assuming a PEG of one. View historical data on ACI Worldwide and its competitors. This is 1774% above median its historical median of 1.72. Over the past decade, ACI Worldwide's Peter Lynch Fair Value has ranged from 0.69 to 40.48. According to the industry distribution chart, ACI Worldwide ranks #379 out of 661 companies in the Software industry, placing it in the top 57.3%.
Is ACI Worldwide's Peter Lynch Fair Value too high?
ACI Worldwide's current Peter Lynch Fair Value of €32.23 is 1774% above median its 10-year median of 1.72. Over the past 10 years, this metric has ranged from a low of 0.69 to a high of 40.48. Based on the distribution chart, ACI Worldwide ranks #379 out of 661 companies in the Software industry, which is below the industry midpoint. Overall, ACI Worldwide has a GF Score™ of 82/100 and is considered Fairly Valued, reflecting its overall financial health beyond just this single metric.
How does ACI Worldwide's Peter Lynch Fair Value compare to PATH and DOX?
According to the Software industry distribution chart, ACI Worldwide ranks #379 out of 661 companies for Peter Lynch Fair Value. This places ACI Worldwide in the lower half of its industry. The industry median Peter Lynch Fair Value is 1.26. Historically, ACI Worldwide's own Peter Lynch Fair Value has ranged from 0.69 to 40.48 over the past decade. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Peter Lynch Fair Value for a Software company?
The median Peter Lynch Fair Value among Software companies is 1.26, based on 661 companies in the industry. Companies in the top quartile (top 25%) have a Peter Lynch Fair Value significantly above this median, while those in the bottom quartile fall well below. However, Peter Lynch Fair Value 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 Peter Lynch Fair Value mean?
A high Peter Lynch Fair Value can signal that a stock is expensive relative to its fundamentals. Peter Lynch Fair Value is the stock value based on a company's current earnings and five-year earnings growth, assuming a PEG of one. View historical data on ACI Worldwide and its competitors. For the Software industry, the median Peter Lynch Fair Value is 1.26 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. ACI Worldwide's current Peter Lynch Fair Value is €32.23, which is 1774% above median its own 10-year median of 1.72. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is ACI Worldwide stock overvalued right now?
Based on GuruFocus' analysis, ACI Worldwide (STU:TSA) is currently considered Fairly Valued. The stock's GF Value™ is €43.79, compared to a current price of €44.40 — trading 1.4% above its estimated fair value. The current Peter Lynch Fair Value is €32.23, which is 1774% above median its 10-year median of 1.72. ACI Worldwide's overall GF Score™ is 82/100 with 2 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Peter Lynch Fair Value calculated?
Peter Lynch Fair Value is calculated from a company's financial statements. For ACI Worldwide (STU:TSA), the current Peter Lynch Fair Value is €32.23 as of Aug. 20, 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 ACI Worldwide (STU:TSA) Overvalued in 2026?
Based on GuruFocus' analysis, ACI Worldwide stock appears to be overvalued.
The current stock price of €44.40 is trading 1.4% above its estimated GF Value™ of €43.79.
GuruFocus considers ACI Worldwide to be Fairly Valued.
Key valuation signals for STU:TSA:
Peter Lynch Fair Value: €32.23 (1774% above median its 10-year median of 1.72)
GF Value™: €43.79 vs. price of €44.40 (1.4% above fair value)
No single metric tells the full story. See the STU:TSA stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
ACI Worldwide Inc develops, markets, and installs a portfolio of software products focused on facilitating electronic payments. The firm's products are sold and supported directly and through distribution networks covering three geographic regions - the Americas, EMEA, and Asia Pacific. ACI software products process payment transactions for retail banking clients, billers such as utilities and healthcare providers, and community banks and credit unions. ACI's customers are financial institutions all over the world, but the majority of the revenue is generated in the United States and EMEA regions. The company's operating segment includes Payment Software and Biller. The company generates the majority of its revenue from the Payment Software segment.
82GF Score
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