How to shade bars in bar graph by axis?

Question

How to shade this graph by 2008 as a cut point? Like, before 2008 all share one color, after 2008 use another color.

Please make a [reproducible example](https://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example) or [minimal reproducible example](https://stackoverflow.com/help/minimal-reproducible-example) with a sample input. This is needed to create, test and verify possible solutions. — Martin Gal, Oct 23 '21 at 22:59

score 1 · Answer 1 · answered Oct 24 '21 at 01:48

you need a vector that is the length of the amount of bars that you have that supplies the color. you could try something like this:

color = ifelse(date < 2008, 'red', 'green')

you have to adjust the test accordingly.

Then you provdide the color to the plot

ggplot(aes(fill = color))

score 0 · Answer 2 · answered Oct 23 '21 at 23:10

you need to use annotate function with rect as the option for geom:

# Add rectangles
p + annotate(
  geom = "rect", 
  xmin=c(2,4), 
  xmax=c(3,5), 
  ymin=c(20,10), 
  ymax=c(30,20), 
  alpha=0.2, 
  color="blue", 
  fill="blue"
)

See https://www.r-graph-gallery.com/233-add-annotations-on-ggplot2-chart.html

How to shade bars in bar graph by axis?

2 Answers2