Add coloured underline in the text in bar-chart - r

Question

Let say I have below bar chart
require(ggplot2)
require(dplyr)
df <- data.frame (Origin = c("Canada", "Canada","USA","USA"),
Year = c("2021", "2022","2021","2022"),
Sales = c(103, 192, 144, 210),
diff = c(89, " ",66," "),
perdiff = c(86.4, " ",45.83," "))
df <- df %>% mutate(label= ifelse(diff!=" ",paste0(diff,", ",perdiff,'%'),NA))
ggplot(df, aes(fill=Year, y=Origin, x=Sales)) +
geom_bar(position="dodge", stat="identity")+
geom_text(aes(label=label, x=200), fontface='bold') +
scale_x_continuous(breaks=seq(0,200,25))+
theme()
While this is fine, I want to add coloured underline under the figures (e.g. 89, 86.4%) which are displayed at the right side of each bar. I should also be able to control the width of such an underline.
Is there any way to achieve this programmatically?
Any pointer will be really helpful

Answer 1

Not sure what you mean by "control the width of such an underline". But one option to add colored underlines to your labels would to add your colored underlines a second geom_text where I use plotmath's underline and phantom to just add the underlines.
library(ggplot2)
library(dplyr)
df <- df %>%
mutate(label = ifelse(diff != " ", paste0(diff, ", ", perdiff, "%"), NA)) %>%
mutate(label1 = ifelse(diff != " ", paste0("underline(bold(phantom(\"", diff, ", ", perdiff, "%", "\")))"), NA))
ggplot(df, aes(fill = Year, y = Origin, x = Sales)) +
geom_bar(position = "dodge", stat = "identity") +
geom_text(aes(label = label, x = 200), fontface = "bold") +
geom_text(aes(label = label1, x = 200), color = "red", parse = TRUE) +
scale_x_continuous(breaks = seq(0, 200, 25))
#> Warning: Removed 2 rows containing missing values (geom_text).
#> Removed 2 rows containing missing values (geom_text).
EDIT To add some padding between the label and the line you could increase the vjust in the second geom_text, e.g.:
ggplot(df, aes(fill = Year, y = Origin, x = Sales)) +
geom_bar(position = "dodge", stat = "identity") +
geom_text(aes(label = label, x = 200), fontface = "bold") +
geom_text(aes(label = label1, x = 200), color = "red", parse = TRUE, vjust = 1) +
scale_x_continuous(breaks = seq(0, 200, 25))