Display Percentage on ggplot Bar Chart in R

Question

I need display the percentage value on the bars of a bar chart in R.

This code plots categorical data, with the categories on x and % on y. How to modify it such that it displays the percentage on the bars themselves, not just on the y-axis?

ggplot(data = iris) + 
  geom_bar(mapping = aes(x = Species, y = (..count..)/sum(..count..), fill = Species)) +
  scale_y_continuous(labels = percent)

Have a look at the `scales` package for the axis labels, and `geom_text` for adding text to the bars. — Andrew Gustar, Sep 17 '18 at 17:35
I've tried adding 'geom_text(aes(label = paste0(100*((..count..)/sum(..count..)))),size = 5)' for the text, but I got an error: Error in sum(count) : invalid 'type' (closure) of argument — Bayram Sarilmaz, Sep 17 '18 at 17:42
Ah, I see what you're saying. You want text on the bars themselves, right? — divibisan, Sep 17 '18 at 17:57
@divibisan yes, exactly....edited the question to clarify this — Bayram Sarilmaz, Sep 17 '18 at 17:58
See [this question](https://stackoverflow.com/q/46262591/5325862) in addition to the one that was posted before as a dupe — camille, Sep 17 '18 at 18:19

Mako212 · Accepted Answer · 2018-09-17T18:11:41.843

The ..count.. helpers in ggplot can be good for simple cases, but it's usually better to aggregate the data at the appropriate level first, not in your ggplot call:

library(tidyverse)
library(scales)

irisNew <- iris %>% group_by(Species) %>% 
 summarize(count = n()) %>%  # count records by species
 mutate(pct = count/sum(count))  # find percent of total

ggplot(irisNew, aes(Species, pct, fill = Species)) + 
  geom_bar(stat='identity') + 
  geom_text(aes(label=scales::percent(pct)), position = position_stack(vjust = .5))+
  scale_y_continuous(labels = scales::percent)

vjust = .5 centers the labels in each bar

Shirin Yavari · Answer 2 · 2018-09-17T18:13:18.693

1

ggplot(data = iris, aes(x = factor(Species), fill = factor(Species))) +
geom_bar(aes(y = (..count..)/sum(..count..)),
         position = "dodge") + 
geom_text(aes(y = (..count..)/sum(..count..), 
              label = paste0(prop.table(..count..) * 100, '%')), 
          stat = 'count', 
          position = position_dodge(.9), 
          size = 3)+ 
labs(x = 'Species', y = 'Percent', fill = 'Species')

edited Sep 17 '18 at 18:13

answered Sep 17 '18 at 17:49

Shirin Yavari

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I get this error: _Error in layer(data = data, mapping = mapping, stat = stat, geom = GeomText, : object '..count..' not found_ – Bayram Sarilmaz Sep 17 '18 at 17:52
1

The `..` notation was deprecated a few versions back in favor of `stat()` – camille Sep 17 '18 at 18:15

Display Percentage on ggplot Bar Chart in R

2 Answers2