The Trend Line ŷT = 125 + 2t and Seasonal $$\begin{array} { | c c | } \hline \text { Quarter } & S I _ { t } \\\hline 1 & 0.6 \\2 & 1.3 \\3 & 1.6 \\4 & 0.5 \\\hline\end{array}$$

Essay

The trend line ŷt = 125 + 2t and seasonal indexes shown below were computed from 10 years of quarterly data. Forecast the values for the next four quarters. $$\begin{array} { | c c | } \hline \text { Quarter } & S I _ { t } \\\hline 1 & 0.6 \\2 & 1.3 \\3 & 1.6 \\4 & 0.5 \\\hline\end{array}$$