2.6.Methods of Forecasting Stationary Series Exponential Smoothing-the current forecast is weighted average of the last forecast and the last value of demand. new forecast a(current observation of demand)+(1-a)(Last forecast) E,=aD,-1+(1-a)E,-1 where 0<a1 is the smoothing constant,which determines the relative weight placed on the last observation of demand, while 1-a is weight placed on the last forecast. F=aD,-1+(1-a)F,-=F-1-a(F-1-D-i)=F-1-Ce-lExponential Smoothing -the current forecast is weighted average of the last forecast and the last value of demand. 1 1 ( ) (1 )(Last forecast) (1 ) tt t new forecast current observation of demand FD F           where 0<1 is the smoothing constant, which determines the relative weight placed on the last observation of demand, while 1-  is weight placed on the last forecast. 1 1 FD F tt t      (1 )  2.6. Methods of Forecasting Stationary Series 1 11 ( )  F FD t tt       F e t t 1 1   