Which key performance indicator helps investors evaluate cost control?

The operating expenses ratio is pivotal for investors assessing a company's cost control efficiency. This indicator measures the proportion of a company's operating expenses relative to its revenue, allowing analysts to understand how well a company manages its operating costs in relation to its income. A lower operating expenses ratio signifies better cost control, indicating that a company is able to maintain or even reduce its expenses while generating revenue, which can lead to improved profitability.

Understanding this ratio helps investors gauge operational efficiency and effectiveness in managing day-to-day expenses. In contrast, other indicators like net profit margin assess overall profitability, revenue growth rate focuses on sales performance, and return on equity looks at the efficiency with which a company generates profit from shareholders' equity, but they do not directly evaluate cost control. Hence, the operating expenses ratio is the most relevant metric for that specific evaluation.