Given the Following Data, Calculate the Three-Year Moving Averages for Years

Essay

Given the following data, calculate the three-year moving averages for years 4 through 10.
$$\begin{array} { | c | c | } \hline \text { Year } & \text { Demand } \\\hline 1 & 74 \\\hline 2 & 90 \\\hline 3 & 59 \\\hline 4 & 91 \\\hline 5 & 140 \\\hline 6 & 98 \\\hline 7 & 110 \\\hline 8 & 123 \\\hline 9 & 99 \\\hline\end{array}$$