For 1985-1995, production in the energy sector included the quantities shown here. The variables and their units are total nonrenewable energy production (quadrillion Btu), crude oil (million bbl per day), natural gas (trillion cubic feet), coal (million short tons), and nuclear power (billion kWh). The data are also in file XR17045.
For these data, and with y = total nonrenewable energy production, generate the correlation matrix for the independent variables and comment on the possible presence of multicollinearity.
