Chang Jia M&E EngineeringROCO:4550 -1.02%58 Operating Margin % is 8.42% as of Dec. 2025, which is 42% above its 10-year median of 5.93. GuruFocus rates ROCO:4550 with a GF Score™ of 58/100 and a GF Value™ of NT$17.77 (Significantly Overvalued). The stock has 4 warning signs investors should review. Among 1,767 Construction companies, Chang Jia M&E Engineering ranks worse than 51.39% on this metric.
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.
Chang Jia M&E Engineering Operating Margin % Related Terms
Chang Jia M&E Engineering Operating Margin % 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.
ROCO:4550 vs PWR, FIX, EME: Operating Margin % Comparison
For the Engineering & Construction subindustry, Chang Jia M&E Engineering'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.
Chang Jia M&E Engineering Operating Margin % vs Construction Industry
For the Construction industry and Industrials sector, Chang Jia M&E Engineering's Operating Margin % distribution charts can be found below:
* The bar in red indicates where Chang Jia M&E Engineering'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.
Chang Jia M&E Engineering'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.
Chang Jia M&E Engineering (ROCO:4550) has a Operating Margin % of 8.42% as of Dec. 2025. Operating margin is the ratio of total operating income to net sales. View historical data on Chang Jia M&E Engineering and its competitors. This is 42% above median its historical median of 5.93. Over the past decade, Chang Jia M&E Engineering's Operating Margin % has ranged from 3.23 to 10.88. According to the industry distribution chart, Chang Jia M&E Engineering ranks #908 out of 1767 companies in the Construction industry, placing it in the top 51.4%.
Is Chang Jia M&E Engineering's Operating Margin % too high?
Chang Jia M&E Engineering's current Operating Margin % of 8.42% is 42% above median its 10-year median of 5.93. Over the past 10 years, this metric has ranged from a low of 3.23 to a high of 10.88. The Construction industry median Operating Margin % is 5.89. Chang Jia M&E Engineering's value of 8.42% is 43% above this industry median. Based on the distribution chart, Chang Jia M&E Engineering ranks #908 out of 1767 companies in the Construction industry, which is below the industry midpoint. Overall, Chang Jia M&E Engineering has a GF Score™ of 58/100 and is considered Significantly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Chang Jia M&E Engineering's Operating Margin % compare to PWR and FIX?
According to the Construction industry distribution chart, Chang Jia M&E Engineering ranks #908 out of 1767 companies for Operating Margin %. This places Chang Jia M&E Engineering in the lower half of its industry. The industry median Operating Margin % is 5.89. Chang Jia M&E Engineering's value of 8.42% is 43% above this benchmark. Historically, Chang Jia M&E Engineering's own Operating Margin % has ranged from 3.23 to 10.88 over the past decade. While the company's 10-year median is 5.93 vs. the industry median of 5.89, Chang Jia M&E Engineering 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 Construction company?
The median Operating Margin % among Construction companies is 5.89, based on 1,767 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. Chang Jia M&E Engineering's current Operating Margin % of 8.42% is 43% 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 Chang Jia M&E Engineering and its competitors. For the Construction industry, the median Operating Margin % is 5.89 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Chang Jia M&E Engineering's current Operating Margin % is 8.42%, which is 42% above median its own 10-year median of 5.93. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Chang Jia M&E Engineering stock overvalued right now?
Based on GuruFocus' analysis, Chang Jia M&E Engineering (ROCO:4550) is currently considered Significantly Overvalued. The stock's GF Value™ is NT$17.77, compared to a current price of NT$24.30 — trading 36.7% above its estimated fair value. The current Operating Margin % is 8.42%, which is 42% above median its 10-year median of 5.93 and 43% above the Construction industry median of 5.89. Chang Jia M&E Engineering's overall GF Score™ is 58/100 with 4 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 Chang Jia M&E Engineering (ROCO:4550), the current Operating Margin % is 8.42% 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 Chang Jia M&E Engineering (ROCO:4550) Overvalued in 2026?
Based on GuruFocus' analysis, Chang Jia M&E Engineering stock appears to be overvalued.
The current stock price of NT$24.30 is trading 36.7% above its estimated GF Value™ of NT$17.77.
GuruFocus considers Chang Jia M&E Engineering to be Significantly Overvalued.
Key valuation signals for ROCO:4550:
Operating Margin %: 8.42% (42% above median its 10-year median of 5.93)
GF Value™: NT$17.77 vs. price of NT$24.30 (36.7% above fair value)
Industry Position: 43% above the Construction median (#908 of 1767)
No single metric tells the full story. See the ROCO:4550 stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Chang Jia M&E Engineering Corp is a Taiwan-based company engaged in the planning, design and engineering contracting of electrical, drainage and air conditioning equipment for various commercial buildings and factories, as well as the operation of sports centers and the import and export of the above-mentioned equipment.
58GF Score
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