Siamrajathanee PCLBKK:SO 88 Operating Margin % is 8.37% as of Mar. 2026, which is 8% above its 10-year median of 7.74. GuruFocus rates BKK:SO with a GF Score™ of 88/100 and a GF Value™ of ฿5.68 (Modestly Undervalued). The stock has 5 warning signs investors should review. Among 1,070 Business Services companies, Siamrajathanee PCL ranks better than 57.1% 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.
Siamrajathanee PCL Operating Margin % Related Terms
Siamrajathanee PCL Operating Margin % Historical Data
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The historical data trend for Siamrajathanee PCL'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.
BKK:SO vs CTAS, CPRT, GPN: Operating Margin % Comparison
For the Specialty Business Services subindustry, Siamrajathanee PCL'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.
Siamrajathanee PCL Operating Margin % vs Business Services Industry
For the Business Services industry and Industrials sector, Siamrajathanee PCL's Operating Margin % distribution charts can be found below:
* The bar in red indicates where Siamrajathanee PCL'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.
Siamrajathanee PCL'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.
Siamrajathanee PCL (BKK:SO) has a Operating Margin % of 8.37% as of Mar. 2026. Operating margin is the ratio of total operating income to net sales. View historical data on Siamrajathanee PCL and its competitors. This is near median its historical median of 7.74. Over the past decade, Siamrajathanee PCL's Operating Margin % has ranged from 5.02 to 9.29. According to the industry distribution chart, Siamrajathanee PCL ranks #459 out of 1070 companies in the Business Services industry, placing it in the top 42.9%.
Is Siamrajathanee PCL's Operating Margin % too high?
Siamrajathanee PCL's current Operating Margin % of 8.37% is near median its 10-year median of 7.74. Over the past 10 years, this metric has ranged from a low of 5.02 to a high of 9.29. The Business Services industry median Operating Margin % is 6.33. Siamrajathanee PCL's value of 8.37% is 32.2% above this industry median. Based on the distribution chart, Siamrajathanee PCL ranks #459 out of 1070 companies in the Business Services industry, which is above the industry midpoint. Overall, Siamrajathanee PCL has a GF Score™ of 88/100 and is considered Modestly Undervalued, reflecting its overall financial health beyond just this single metric.
How does Siamrajathanee PCL's Operating Margin % compare to CTAS and CPRT?
According to the Business Services industry distribution chart, Siamrajathanee PCL ranks #459 out of 1070 companies for Operating Margin %. This puts Siamrajathanee PCL in the upper half of its industry. The industry median Operating Margin % is 6.33. Siamrajathanee PCL's value of 8.37% is 32.2% above this benchmark. Historically, Siamrajathanee PCL's own Operating Margin % has ranged from 5.02 to 9.29 over the past decade. While the company's 10-year median is 7.74 vs. the industry median of 6.33, Siamrajathanee PCL 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 Business Services company?
The median Operating Margin % among Business Services companies is 6.33, based on 1,070 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. Siamrajathanee PCL's current Operating Margin % of 8.37% is 32.2% 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 Siamrajathanee PCL and its competitors. For the Business Services industry, the median Operating Margin % is 6.33 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Siamrajathanee PCL's current Operating Margin % is 8.37%, which is near median its own 10-year median of 7.74. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Siamrajathanee PCL stock overvalued right now?
Based on GuruFocus' analysis, Siamrajathanee PCL (BKK:SO) is currently considered Modestly Undervalued. The stock's GF Value™ is ฿5.68, compared to a current price of ฿4.64 — trading 18.3% below its estimated fair value. The current Operating Margin % is 8.37%, which is near median its 10-year median of 7.74 and 32.2% above the Business Services industry median of 6.33. Siamrajathanee PCL's overall GF Score™ is 88/100 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 Siamrajathanee PCL (BKK:SO), the current Operating Margin % is 8.37% 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 Siamrajathanee PCL (BKK:SO) Overvalued in 2026?
Based on GuruFocus' analysis, Siamrajathanee PCL stock appears to be undervalued.
The current stock price of ฿4.64 is trading 18.3% below its estimated GF Value™ of ฿5.68.
GuruFocus considers Siamrajathanee PCL to be Modestly Undervalued.
Key valuation signals for BKK:SO:
Operating Margin %: 8.37% (near median its 10-year median of 7.74)
GF Value™: ฿5.68 vs. price of ฿4.64 (18.3% below fair value)
Industry Position: 32.2% above the Business Services median (#459 of 1070)
No single metric tells the full story. See the BKK:SO stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Siamrajathanee PCL is an outsourcing services company in Thailand for both the government and private sectors. It is principally engaged in providing outsourcing services and vehicle operating lease services. The company, along with its subsidiaries, is organized into business units based on its products and services and has the following reportable segments: the Outsourcing service segment, the Rental service segment, and others. A majority of its revenue is generated from the Outsourcing service segment, which provides services like Workforce management, corporate car rental, landscape maintenance, and industrial waste disposal. Geographically, the group operates only in Thailand.
88GF Score
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