(10 points total)

5. The data below provides monthly sales for 18 months.

Month	Sales
21	3,524
22	3,245
23	3,658
24	4,123
25	3,955
26	4,188
27	4,644
28	4,372
29	4,955
30	4,617
31	4,639
32	5,120
33	4,765
34	5,023
35	5,298
36	5,121
37	5,689
38	5,534

(2 pts.) a) Use a four period weighted moving average with weights of 0.5, 0.30 and 0.20 to forecast the month 39 sales.

Forecast of sales for month 39 = ________

(4 pts.) b) What is the linear regression equation for forecasting, and what is the R² value?

Equation: ________________

R = ________

(3 pts.) c) Use linear regression to make a forecast for months 39 and 48.

Forecast of sales for month 39 = ________

Forecast of sales for month 48 = ________

(1 pts) d) What about this data above will make a linear regression forecast generally greater than a weighted moving average forecast?