Understanding Return on Investment
Return on Investment (ROI) is a performance measure used to evaluate the efficiency or profitability of an investment. It is an incredibly versatile financial metric used in everything from evaluating stock market investments to analyzing the success of a marketing campaign or a real estate purchase.
ROI directly answers the question: "For every dollar I put into this endeavor, how much did I get back?" A positive ROI means the investment generated a profit, while a negative ROI means you lost money.
How is ROI Calculated?
The formula for ROI is simple: subtract the initial cost of the investment from the final return to find the net profit. Then, divide the net profit by the initial cost of the investment. Finally, multiply by 100 to express the result as a percentage.
Formula: ROI = ((Total Return - Investment Cost) / Investment Cost) × 100
For example, if you buy $1,000 worth of stock and sell it for $1,200, your net profit is $200. Your ROI is ($200 / $1,000) × 100 = 20%.
The Limitations of Basic ROI
While basic ROI is an excellent quick-glance metric, it does not account for the holding period (time). A 20% return over one month is an incredible investment, but a 20% return over ten years is very poor when compared to average market returns and inflation.
When evaluating long-term investments, analysts often use Annualized ROI or metrics like the Internal Rate of Return (IRR) which factor in the time value of money.