Mean absolute percentage error

Mean absolute percentage error (also known as MAPE) is measure of accuracy in a fitted time series value in statistics, specifically trending. It usually expresses accuracy as a percentage.

$$\mbox{MAPE} = \frac{1}{n}\sum_{t=1}^n \left| \frac{A_t-F_t}{A_t}\right|.$$

. M.A.P.E. gives accuracy of forecasts.

% error = ((Actual value - forecast)/ Actual value )* 100 M.A.P.E = summation of absolute value of % errors / n

where n =no of periods for which forecasts are generated.

for various experiments M.A.P.E =< 20% is acceptable.