Basic Econometrics 5th Edition by Damodar Gujarati,Dawn Porter

Exercise 16

Using the U.S. economic time series data posted on the book's website, obtain sample correlograms up to 36 lags for the time series LPCE, LDPI, LCP(profits), and LDIVIDENDS. What general pattern do you see Intuitively, which one(s) of these time series seems to be stationary