I would like to create a stacked bar graph with ggplot where the heights of the bars depend on the values of one variable (voter turnout in %) and the stacks of the bars individually add up to 100% of another variable (voteshare in %). So for the year 1990 there was a voter turnout of 96.7 and the bar should be filled with the individual voteshares of each party, which add up to 100% (of the 96.7%). I look at the data of 3 parties and 3 years.
Here is my data:
party <- c("a", "b", "c", "a", "b", "c", "a", "b", "c")
year <- c(1990, 1990, 1990, 1991, 1991, 1991, 1992,1992, 1992)
voteshare <- c(0,33.5, 66.5, 40.5, 39.0, 20.5, 33.6, 33.4, 33)
turnout = c(96.7,96.7,96.7, 85.05,85.05,85.05, 76.41, 76.41, 76.41)
df<- data.frame(parties, year, voteshare, turnout)
In addition, I would like to put the numbers of the individual voteshares and the total turnout inside the graph.
My approach so far:
ggplot(df, aes(x=year, y=interaction(turnout, voteshare), fill=party)) +
geom_bar(stat="identity", position=position_stack()) +
geom_text(aes(label=Voteshare), vjust=0.5)
It's a mess.
Thanks a ton in advance!
I used a dplyr
pipeline to:
cumsum()
of vote share by party, grouped by year. I had to use rev()
because the default of position_stack()
is to put the low number in alphabetical order at the top of the stack.Code
library(dplyr)
library(ggplot2)
df <- df %>%
mutate(adj_vote = turnout * voteshare / 100) %>%
filter(adj_vote > 0) %>%
group_by(year) %>%
mutate(cum_vote = cumsum(rev(adj_vote)),
vote_label = rev(voteshare))
ggplot(df, aes(x=year, y=adj_vote, fill=party)) +
geom_bar(stat="identity", position=position_stack()) +
geom_text(aes(label=vote_label, y = cum_vote), vjust=0.5)
Output