New Exercise Bank Content Qu$.04-19$

Management of the Jackson Manufacturing Corporation wishes to choose a statistical forecasting method for forecasting total sales for the corporation. Total sales $($in millions of dollars$)$ for each month of last year are shown below.

$\backslash$table$[[$Month$,$Sales$],[$January$,126],[$February$,137],[$March$,142],[$April$,150],[$May$,153],[$June$,154],[$July$,148],[$August$,145],[$September$,147],[$October$,151],[$November$,159],[$December$,166]]$

Apply the last$-$value method, the averaging method, and the moving average method $($with $n=3)$ retrospectively to last year's sales. Then compute the MAD and MSE values for each of the three methods.

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a$.$ Last$-$Value Method:

Note: Round your answers to $1$ decimal place.

$\backslash$table$[[$MAD$,],[$MSE$,]]$