The index of industrial production (IP) is a monthly time series that measures the quantity of industrial commodities produced in a given month. This problem uses data on this index for the United States. All regressions are estimated over the sample period 1960:1 to 2000 12 (that is, January 1960 through December 2000). Let Yt 1200 x In(PtllPt-1). a. The forecaster states that Yt shows the monthly percentage change in IP measured in percentage points per annum. Is this correct? Why?