Problems $16$ through $21$ are based on the following data. Observations of the demand

for a certain part stocked at a parts supply depot during the calendar year $2013$ were

Month Demand Month Demand

January $89$ July $223$

February $57$ August $286$

March $144$ September $212$

April $221$ October $275$

May $177$ November $188$

June $280$ December $312$

$16.$ Determine the one$-$step$-$ahead forecasts for the demand for January $2014$ using

$3-,6-,$ and $12-$month moving averages.