Problem $3-20($Static$)$

In this problem, you are to test the validity of your forecasting model. Here are the forecasts for a model you have been using and the actual demands that occurred:

a$.$ Use the method stated in the text to compute the MAD and tracking signal for each week.

Note: Negative values should be indicated by a minus sign. Round your "Tracking Signal" to $1$ decimal place and all other answers to the nearest whole number.

b$.$ Decide whether the forecasting model you have been using is giving reasonable results.

The forecasting model is acceptable.

The forecasting model is unacceptable.