The president of a small manufacturing firm is concerned about the continual growth in manufacturing costs in the past several years. The data series of the cost per unit for the firm's leading product over the past eight years are given as follows:
Year Cost/Unit ($)
1 20
2 24.5
3 28.2
4 27.5
5 26.6
6 30
7 31
8 36

a) Use EXCEL's regression function to develop a simple linear regression model (i.e., write out the equation Y= intercept + slope*year) for these data. What is the average cost increase per year that the firm has been realizing?

b) What is the forecast for year 9?

c) What is MAPE?