Demand for oil changes at Garcia’s Garage has been as follows:
Month Number of Oil Changes
January 41
February 46
March 57
April 52
May 59
June 51
July 60
August 62
Use simple linear regression analysis to develop a forecasting model for monthly demand. In this application, the dependent variable, Y, is monthly demand and the independent variable, X, is the month. For January, let X = 1 X=1; for February, let X = 2 X=2; and so on. Use the model to forecast demand for September, October, and November. Here, X = 9 , 10 X=9,10, and 11, respectively.