Use the data us$\_$private$\_$emp you created in problem $2$ above and create the data set us$\_$private$\_$emp$\_$train that covers the period from January $1990$ to December $2015\mathrm{.}4\mathrm{.}2.$ Fit the models Mean, Na$$ve$,$ Seasonal Na$$ve$,$ and Drift to the original US private employment series$\mathrm{.}4\mathrm{.}3.$ Generate forecasts for the period January $2016-$ September $2019\mathrm{.}4\mathrm{.}4.$ Generate a plot of the forecasts and the actual data. Attach the plot here.

For R programming