An investment's yield is the amount of return that the investment generates over a specified period of time. It is expressed as a percentage based on the invested amount, the current market value, or the face value of the security.
Dividends and interest earned on holding particular security are included in the yield. Yields can be classified as known or anticipated depending on the valuation (fixed versus fluctuating) of the security.

The yield is one of the most importance considerations for investors as it shows the return on the investment over a certain amount of time and since it is given as a percentage it is easily understood and ideal for comparison purposes.