The following data show the time series of the most recent quarterly capital expenditures (in billions of dollars) for the 1000 largest manufacturing firms: 24, 25, 23, 24, 22, 26, 28, 31, 29, 32, 37, and 42.
a. Develop a linear trend equation for the time series.
b. Graph the time series and the linear trend equation.
c. What appears to be happening to capital expenditures? What is the forecast one year, or four quarters, into the future?