Groupe GuillinSTU:ZUY 78 Operating Margin % is 8.47% as of Dec. 2025, which is 20% below its 10-year median of 10.57. GuruFocus rates STU:ZUY with a GF Score™ of 78/100 and a GF Value™ of €28.60 (Modestly Undervalued). The stock has 5 warning signs investors should review. Among 389 Packaging & Containers companies, Groupe Guillin ranks better than 66.32% on this metric.
Groupe Guillin SA operating margin has been in a 5-year decline. The average rate of decline per year is -8.4%.
The historical rank and industry rank for Groupe Guillin's Operating Margin % or its related term are showing as below:
STU:ZUY'
s Operating Margin % Range Over the Past 10 Years
Min: 7.77 Med: 10.57 Max: 13.82
Current: 7.77
STU:ZUY's Operating Margin % is ranked better than 66.32% of 389
companies
in the Packaging & Containers industry
Industry Median: 5.27
vs STU:ZUY: 7.77
Groupe Guillin's 5-Year Average Operating Margin % Growth Rate was -8.40% per year.
Groupe Guillin (STU:ZUY) Operating Margin % Explanation
Just like Gross Margin %, it is important to see a company maintains its operating margin over time. Among the same industry, a company with higher operating margin is more efficient in its operation. It is also more stable during industry slowdown or recessions. Peter Lynch prefers those with higher margins than those with lower margins.
Be Aware
Operating Margin % can be manipulated by adjusting the rate of depreciation, depletion and amortization (DDA).
If a company is facing competition, its Operating Margin % may decline. Often the Operating Margin % declines well before the company's Revenue or even profit decline. Therefore, Operating Margin % is a very important indicator of whether the company is facing problems.
For instance, by 2012, Nokia (NOK)'s problems were well known and its stock had lost more than 90% of its market value since 2007. But Nokias Operating Margin % had already been in decline since 2002, although its Earnings per Share (Diluted) were still rising. Investors who paid attention to Operating Margin % would have avoided this huge loss. The same can be said for Research-in-Motion (RIMM).
Therefore, Operating Margin % is a very important screening filter for GuruFocus. GuruFocus's Buffett-Munger screener requires that the profit margin is either consistent or expanding. The Model Portfolio of the Buffett-Munger screener has outperformed the market every year since inception in 2009.
Groupe Guillin Operating Margin % Related Terms
Groupe Guillin Operating Margin % Historical Data
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The historical data trend for Groupe Guillin's Operating Margin % 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:ZUY vs SW, PKG, IP: Operating Margin % Comparison
For the Packaging & Containers subindustry, Groupe Guillin's Operating Margin %, along with its competitors' market caps and Operating Margin % 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.
Groupe Guillin Operating Margin % vs Packaging & Containers Industry
For the Packaging & Containers industry and Consumer Cyclical sector, Groupe Guillin's Operating Margin % distribution charts can be found below:
* The bar in red indicates where Groupe Guillin's Operating Margin % falls into.
Operating Margin % - also known as operating income margin, operating profit margin and return on sales (ROS) - is the ratio of Operating Income divided by net sales or Revenue, usually presented in percent.
Groupe Guillin's Operating Margin % for the fiscal year that ended in Dec. 2025 is calculated as
* 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.
Groupe Guillin (STU:ZUY) has a Operating Margin % of 8.47% as of Dec. 2025. Operating margin is the ratio of total operating income to net sales. View historical data on Groupe Guillin and its competitors. This is 20% below median its historical median of 10.57. Over the past decade, Groupe Guillin's Operating Margin % has ranged from 7.77 to 13.82. According to the industry distribution chart, Groupe Guillin ranks #131 out of 389 companies in the Packaging & Containers industry, placing it in the top 33.7%.
Is Groupe Guillin's Operating Margin % too high?
Groupe Guillin's current Operating Margin % of 8.47% is 20% below median its 10-year median of 10.57. Over the past 10 years, this metric has ranged from a low of 7.77 to a high of 13.82. The Packaging & Containers industry median Operating Margin % is 5.27. Groupe Guillin's value of 8.47% is 60.7% above this industry median. Based on the distribution chart, Groupe Guillin ranks #131 out of 389 companies in the Packaging & Containers industry, which is above the industry midpoint. Overall, Groupe Guillin has a GF Score™ of 78/100 and is considered Modestly Undervalued, reflecting its overall financial health beyond just this single metric.
How does Groupe Guillin's Operating Margin % compare to SW and PKG?
According to the Packaging & Containers industry distribution chart, Groupe Guillin ranks #131 out of 389 companies for Operating Margin %. This puts Groupe Guillin in the upper half of its industry. The industry median Operating Margin % is 5.27. Groupe Guillin's value of 8.47% is 60.7% above this benchmark. Historically, Groupe Guillin's own Operating Margin % has ranged from 7.77 to 13.82 over the past decade. While the company's 10-year median is 10.57 vs. the industry median of 5.27, Groupe Guillin 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 Operating Margin % for a Packaging & Containers company?
The median Operating Margin % among Packaging & Containers companies is 5.27, based on 389 companies in the industry. Companies in the top quartile (top 25%) have a Operating Margin % significantly above this median, while those in the bottom quartile fall well below. However, Operating Margin % should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Groupe Guillin's current Operating Margin % of 8.47% is 60.7% 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 Operating Margin % mean?
A high Operating Margin % can signal that a stock is expensive relative to its fundamentals. Operating margin is the ratio of total operating income to net sales. View historical data on Groupe Guillin and its competitors. For the Packaging & Containers industry, the median Operating Margin % is 5.27 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Groupe Guillin's current Operating Margin % is 8.47%, which is 20% below median its own 10-year median of 10.57. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Groupe Guillin stock overvalued right now?
Based on GuruFocus' analysis, Groupe Guillin (STU:ZUY) is currently considered Modestly Undervalued. The stock's GF Value™ is €28.60, compared to a current price of €22.60 — trading 21% below its estimated fair value. The current Operating Margin % is 8.47%, which is 20% below median its 10-year median of 10.57 and 60.7% above the Packaging & Containers industry median of 5.27. Groupe Guillin's overall GF Score™ is 78/100 with 5 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Operating Margin % calculated?
Operating Margin % is calculated from a company's financial statements. For Groupe Guillin (STU:ZUY), the current Operating Margin % is 8.47% as of Dec. 2025. 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 Groupe Guillin (STU:ZUY) Overvalued in 2026?
Based on GuruFocus' analysis, Groupe Guillin stock appears to be undervalued.
The current stock price of €22.60 is trading 21% below its estimated GF Value™ of €28.60.
GuruFocus considers Groupe Guillin to be Modestly Undervalued.
Key valuation signals for STU:ZUY:
Operating Margin %: 8.47% (20% below median its 10-year median of 10.57)
GF Value™: €28.60 vs. price of €22.60 (21% below fair value)
Industry Position: 60.7% above the Packaging & Containers median (#131 of 389)
No single metric tells the full story. See the STU:ZUY stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Groupe Guillin SA is a European company. It is engaged in producing and selling of plastic packages. The company's product offering includes trays, catering containers, cake, and pastry containers and thermoforming sheets. The firm serves the catering industry, meat and food industry, and fruit and vegetable producers and packers.
78GF Score
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