Creating stacked bar charts with percentages in R

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# Provided sample data
df <- structure(list(Country = c("Algeria", "Angola", "Benin", "Botswana",
                           "Burkina Faso", "Burundi", "Cameroon", "Cape Verde", "Central African Republic",
                           "Chad"), Authorship = c(273, 1, 34, 70, 35, 7, 88, 11, 0, 6),
               UnAuthorship = c(49, 16, 29, 75, 18, 2, 31, 1, 4, 35), PA = c(84.7826087,
                                                                             5.882352941, 53.96825397, 48.27586207, 66.03773585, 77.77777778,
                                                                             73.94957983, 91.66666667, 0, 14.63414634), PUA = c(15.2173913,
                                                                                                                                94.11764706, 46.03174603, 51.72413793, 33.96226415, 22.22222222,
                                                                                                                                26.05042017, 8.333333333, 100, 85.36585366)), row.names = c(NA,
                                                                                                                                                                                            -10L), class = c("tbl_df", "tbl", "data.frame"))

# Relevant code
library(tidyverse)

df %>% 
    pivot_longer(c("PA", "PUA"), names_to = "type") %>% 
    ggplot(aes(y = Country, x = value, fill = type)) +
    geom_col() +
    scale_x_continuous(labels = scales::percent_format(scale = 1))

Created on 2021-12-05 by the reprex package (v2.0.1)