Problem $3$

A candy production company makes chocolate boxes for which the demand is uncertain. Quarterly demand $($in boxes of chocolate$)$ for the last $3$ years are as follows:

$\backslash$table$[[$Quarter$,$Year $1,$Year $2,$Year $3],[1,3,000,3,300,3,500],[2,1,700,2,100,2,450],[3,900,1,500,1,770],[4,4,400,5,100,5,900]]$

a$.$ Plot the demand data. Does the data appear to be seasonal and have upward or downward trend?

b$.$ Compute the quarterly seasonal indices using the simple average method.

c$.$ De$-$seasonalize the demand data.

d$.$ Develop a linear trend equation using the de$-$seasonalized demand.

e$.$ Develop a trend forecast for quarters $1$ to $4$ of year $4.$

f$.$ Develop a seasonalized forecast for quarters $1$ to $4$ of year $4.$