So I am trying to graph enrollment rates for subgroups within race using bar charts. I have four "cohorts" - an overall cohort, and then the class of 2012, 2013, and 2014. Each grid is one of the four cohorts. I have a dataset with each of the subgroup enrollment rates for each cohort . Then, I have a dataset with the overall rate of enrollment for each cohort. I want the subgroup rates to bars but I want to plot the overall rate as a single line across all bars so you can see what the overall rate was for the overall cohort, class of 2012, 2013, and 2014. I can't seem to figure out how to plot a single line for the overall rate. Each cohort's overall rate is different so I can't just plot the same line across all four grids. Here's what I have. Test has the subgroup rates. Test2 have the overall rates
g <- ggplot(test, aes(x=Group, y= Rate, fill= Group)) +
geom_bar(stat = "identity") +
geom_line(test2, mapping = (aes(x= Group, y = Rate))) +
facet_grid(factor(test$Cohort))