Use the following 12 periods of demand to produce a double exponential smoothing forecast for period 13. Use a smoothing constant, α, equal to 0.35. Use 536 as the initial forecast values.
Period a t
1…………………………536
2…………………………573
3…………………………568
4…………………………640
5…………………………746
6…………………………619
7…………………………772
8…………………………704
9…………………………899
10…………………………863
11…………………………822
12…………………………864