Here is some code to make some plots demonstrating the lie factor that results from using nested donut plots when you should just use a bar chart.

nested_donut_bullshit.R

# Clear. Dat. Workspace.
rm(list = ls())

# Load. Dem. Packages.
library(tidyverse)

# Create. Dat. Data.
dat <- data.frame(category = LETTERS[1:4],
                  fraction = c(0, 20, 30, 50)) # Extra zero datapoint to keep hole in the donut.

# Create a bar chart that isn't bullshit.
not_bullshit<-
  dat[2:4, ] %>%
  ggplot(aes(x = category, y = fraction)) +
  geom_bar(stat = "identity", fill = "gray") +
  geom_hline(yintercept = dat$fraction[2], color = "black") +
  ylim(0, 100) +
  xlab(NULL) +
  ylab(NULL) +
  labs(title = "NOT BULLSHIT",
       subtitle = "Line creates lines of equal length") +
  theme_minimal() +
  theme(panel.grid = element_blank(),
        axis.text.x = element_blank(),
        axis.ticks.x = element_blank())
        
# Put the exact same plot onto polar coordinates for insta-bullshit.
bullshit <-
  not_bullshit %+%
  dat +
  coord_polar(theta = "y", start = pi, direction = 1) +
  theme(axis.text = element_blank(),
        axis.ticks = element_blank(),
        panel.grid  = element_blank()) +
  labs(title = "BULLSHIT",
       subtitle = "Line creates lines of different length")
        
# Compare the non-bullshit to the bullshit.
not_bullshit
bullshit