Data on Demand Over the Last Few Years Are Available

Short Answer

Data on demand over the last few years are available as follows: $$\begin{array} { l l } \text { Time Period } & \text { Demand } \\\hline 7 \text { years ago } & 7 \\6 \text { years ago } & 28 \\\text { 5 years ago } & 21 \\\text { 4 years ago } & 42 \\\text { 3 years ago } & 35 \\\text { 2 years ago } & 56 \\\text { Last year } & 49\end{array}$$ What are this and next year's forecasts using the least squares trend line for these data?