Problem $3-17($Algo$)$

Here are the actual tabulated demands for an item for a nine$-$month period $($January through September$).$ Your supervisor wants to test two forecasting methods to see which method was better over this period.

MONTH ACTUAL

January $98$

February $121$

March $144$

April $176$

May $165$

June $186$

July $146$

August $132$

September $161$

a$.$ Forecast April through September using a three$-$month moving average.

Note: Round your answers to $2$ decimal places.

b$.$ Use simple exponential smoothing with an alpha of $0\mathrm{.}20$ to estimate April through September, using the average of January through March as the initial forecast for April.

Note: Round your answers to $2$ decimal places.

c$-1.$ Calculate MAD for each method.

Note: Round your answers to $2$ decimal places.