Refer to the following table which contains the sales (in $,000) for a department store for the first ten months of the year.

Refer to the following table which contains the sales (in $,000) for a department store for the first ten months of the year.

Month

Sales

January

440

February

480

March

590

April

400

May

500

June

550

July

470

August

500

September

600

October

520

Using a three period moving average (i.e. MA(3)) as a forecasting method, what is the MAD for this forecasting model?