Return on Investment (ROI).

Return on investment (ROI) is one of the most widely used financial metrics in business and personal investing, expressing the profit or loss generated by an investment as a percentage of its cost. The basic formula is straightforward: (net profit ÷ cost of investment) × 100. Because the calculation is simple and produces a single comparable percentage, ROI appears across contexts ranging from corporate capital budgeting to marketing spend analysis to personal investing benchmarks. In a business setting, ROI helps decision-makers prioritize competing uses of capital — a marketing campaign with a 200% ROI is generally more attractive than an equipment purchase yielding 40%, all else equal. In real estate, ROI typically incorporates rental income, appreciation, and costs such as maintenance, taxes, and financing. In equity investing, ROI can refer to the total return on a stock or fund position, including dividends and capital appreciation. The metric's simplicity is also its primary limitation: ROI ignores the time dimension. A 50% return over one year and a 50% return over ten years have identical ROI figures but dramatically different annualized compound growth rates. For time-sensitive decisions, analysts supplement ROI with internal rate of return or net present value, which account for how long capital is tied up. ROI also omits risk — a higher ROI on a speculative venture may represent worse expected value than a lower ROI on a low-risk asset. Despite these shortcomings, ROI remains a universal starting point for evaluating whether an investment is worth making, communicating results to non-specialists, and benchmarking performance across departments or asset classes with very different characteristics.