The average yield on an investment or a portfolio that results from adding all interest, dividends or other income generated from the investment, divided by the average of the investments for the year. The average annual yield is a particularly useful tool for floating-rate investments, in which the fund's balance and/or the interest rate change frequently. 
 
|||For example, for a savings account that pays a floating rate of interest on balances, the average yield can be calculated by adding all interest payments for the year and dividing that number by the average balance for the year. The average annual yield is a backward-looking measurement and can be very useful in determining the actual performance of a mixture of investments.