Return on Investment (ROI) Calculator

Return on investment is a ratio, not a rate: net profit divided by total cost, where total cost includes the initial outlay plus any additional costs such as fees, commissions, renovation or carrying expenses. Because the denominator is a choice rather than a fact, two analysts can compute very different ROIs on identical cash flows simply by including or excluding transaction costs, so stating what went into the base is part of reporting the number honestly. The plain ratio also carries no time information, which is why the annualized figure exists. Raising the ratio of final value to total cost to the power of 1 divided by the number of years and subtracting 1 gives the compound annual growth rate - the constant yearly rate that would have produced the same ending value. A 50 percent total return means something entirely different over one year than over ten: the same 50 percent annualizes to 50 percent in the first case and about 4.1 percent in the second. For benchmarking, US large-cap equities have returned roughly 10 percent per year in nominal terms over the long run, near 7 percent after inflation, so annualized figures far above that deserve scrutiny. The main limitations are that ROI ignores the timing and reinvestment of interim cash flows, which internal rate of return and net present value handle properly; it says nothing about risk or volatility; and unless inflation is subtracted the result is a nominal return rather than a gain in purchasing power.

Return on investment as a management metric was engineered inside a single company. Around 1912 to 1914, Donaldson Brown, an electrical engineer working in the treasury department of the DuPont Powder Company, formulated what became the DuPont identity: return on investment equals profit margin multiplied by asset turnover. Splitting the ratio this way let DuPont see whether a division was earning through pricing or through efficient use of capital, and it turned a single accounting figure into a diagnostic. When DuPont took a large stake in General Motors, Brown moved there as chief financial officer in 1921 and installed the same system under Alfred Sloan, where it became the backbone of divisional performance control. Through the mid-twentieth century ROI spread as the standard yardstick for decentralized corporations, a development the business historian Alfred Chandler documented as central to the multidivisional firm. Its shortcomings then drove the next generation of tools. Joel Dean's Capital Budgeting in 1951 argued for discounted cash flow methods that respect the timing of money, and in 1980 Robert Hayes and William Abernathy published Managing Our Way to Economic Decline in the Harvard Business Review, arguing that ratio-driven management encouraged short-horizon decisions. Value-based measures such as economic value added, commercialized by Stern Stewart in the 1980s, were later responses to the same critique.