Steps for

Problem $18-23($Algo$)$

After using your forecasting model for six months, you decide to test it using MAD and a tracking signal. Here are the forecast and actual demands for the six$-$month period:

$\backslash$table$[[$PERIOD$,$FORECAST,ACTUAL$],[$May$,440,505],[$June$,490,535],[$July$,540,405],[$August$,605,495],[$September$,655,665],[$October$,680,605]]$

a$.$ Find the tracking signal.

Note: Negative values should be indicated by a minus sign. Round your answers to $2$ decimal places.

$\backslash$table$[[$Period$,$Tracking Signal$],[$May$,0\mathrm{.}89],[$June$,],[$July$,],[$August$,],[$September$,],[$October$,]]$