A return, in investing, is the profit or loss made on an investment over a stated period, expressed as a percentage of its starting value. It combines the change in price with any income received, such as a dividend or interest payment. The simple return is , where is the starting price, the ending price and the income paid during the period. A share bought at $100, sold at $108 after paying a $2 dividend, returned percent. A return that includes income is called a total return.
Quantitative work often uses the logarithmic return, the natural log of the ending value over the starting value, because log returns add up across periods. Returns over different horizons are compared by converting them to an annualized return. A return means little without reference to the risk taken, so it is commonly judged against a benchmark such as the market return or as a risk-adjusted return.