The following data list worldwide shipments of personal computers (in thousands) according to Dataquest. 

YearShipments (in '000)

1990..........23,738

1991..........26,966

1992..........32,411

1993..........38,851

1994..........47,894

1995..........60,171

1996...........71,065

1997.........82,400

1998.........97,321

(a) Use exponential smoothing to determine the forecast of shipments for the year 1999. Use the actual shipments for 1990 as the starting forecast for

1991. Use a smoothing constant of α = 0.4. 

b. Plot the data, fit a trend line, display equation and R2 on the chart and discuss the strength of prediction of the regression model. Note: Use X = 1 to represent Year 1990, X = 2 to represent Year 1991, and so on to get more accurate equation.

c. Use the regression model to predict the shipments for the years 1992 through 1999.

d. Which forecasting method would you prefer to use and why? Note: Compute MAPE for the two forecasting methods to compare the accuracy for the period 1992-1998.