I am plotting sales over years of variable x over the years. I already have a variable "quarters" indicating quarter 1,2,3 or 4.
With the following code i plotted unit sales over the years:
ggplot(data = hoogvliet_tess ,aes(x=date, y=UnitSales)) + geom_line() + ggtitle("UnitSales x over the years")
Is there a possibility to extent the plot with for example vertical lines indicating the quarters of every year?
With kind regard,