Return on Investment (ROI)

Return on Investment (ROI) is a performance measure used to evaluate the efficiency of an investment or compare the efficiency of a number of different investments. ROI tries to directly measure the amount of return on a particular investment, relative to the investment’s cost. To calculate ROI, the benefit (or return) of an investment is divided by the cost of the investment. The result is expressed as a percentage or a ratio.

The return on investment formula:

ROI = (Current Value of Investment - Cost of Investment) / Cost of Investment

In the above formula, "Current Value of Investment” refers to the proceeds obtained from the sale of the investment of interest. Because ROI is measured as a percentage, it can be easily compared with returns from other investments, allowing one to measure a variety of types of investments against one another.

ROI is a popular metric because of its versatility and simplicity. Essentially, ROI can be used as a rudimentary gauge of an investment’s profitability. This could be the ROI on a stock investment, the ROI a company expects on expanding a factory, or the ROI generated in a real estate transaction. The calculation itself is not too complicated, and it is relatively easy to interpret for its wide range of applications. If an investment’s ROI is net positive, it is probably worthwhile. But if other opportunities with higher ROIs are available, these signals can help investors eliminate or select the best options. Likewise, investors should avoid negative ROIs, which imply a net a loss.

For example, suppose Joe invested $1,000 in Slice Pizza Corp. in 2017 and sold his stock shares for a total of $1,200 one year later. To calculate his return on his investment, he would divide his profits ($1,200 - $1,000 = $200) by the investment cost ($1,000), for a ROI of $200/$1,000, or 20 percent.

With this information, he could compare his investment in Slice Pizza with his other projects. Suppose Joe also invested $2,000 in Big-Sale Stores Inc. in 2014 and sold his shares for a total of $2,800 in 2017. The ROI on Joe’s holdings in Big-Sale would be $800/$2,000, or 40 percent. (See Limitations of ROI below for potential issues arising from contrasting time frames.)

Examples like Joe's (above) reveal some limitations of using ROI, particularly when comparing investments. While the ROI of Joe’s second investment was twice that of his first investment, the time between Joe’s purchase and sale was one year for his first investment and three years for his second.

Joe could adjust the ROI of his multi-year investment accordingly. Since his total ROI was 40 percent, to obtain his average annual ROI, he could divide 40 percent by 3 to yield 13.33 percent. With this adjustment, it appears that although Joe’s second investment earned him more profit, his first investment was actually the more efficient choice.

ROI can be used in conjunction with Rate of Return, which takes in account a project’s time frame. One may also use Net Present Value (NPV), which accounts for differences in the value of money over time, due to inflation. The application of NPV when calculating rate of return is often called the Real Rate of Return.

Recently, certain investors and businesses have taken an interest in the development of a new form of the ROI metric, called "Social Return on Investment," or SROI. SROI was initially developed in the early 2000s and takes into account broader impacts of projects using extra-financial value (i.e. social and environmental metrics not currently reflected in conventional financial accounts). SROI helps understand the value proposition of certain ESG (Environmental Social & Governance) criteria used in socially responsible investing (SRI) practices. For instance, a company may undertake to recycle water in its factories and replace its lighting with all LED bulbs. These undertakings have an immediate cost which may negatively impact traditional ROI - however, the net benefit to society and the environment could lead to a positive SROI

There are several other new flavors of ROI that have been developed for particular purposes. Social media statistics ROI pinpoints the effectiveness of social media campaigns - for example how many clicks or likes are generated for a unit of effort. Similarly, marketing statistics ROI tries to identify the return attributable to advertising or marketing campaigns. So-called learning ROI relates to amount of information learned and retained as return on education or skills training. As the world progresses and the economy changes, several other niche forms of ROI are sure to be developed in the future.