Drupal 8 inheritance hierarchy depth

library(ggplot2)
library(plyr)

df <- read.csv("~/d8_inheritence_depth.csv")

totals <- ddply(df, ~furthest_parent, summarise, sum = sum(depth), mean = mean(depth), 
    sd = sd(depth))

ggplot(df[df$depth > 1, ], aes(furthest_parent, depth, fill = furthest_parent, 
    alpha = 0.5)) + geom_boxplot() + coord_flip() + xlab("First class in hierarchy") + 
    ylab("Inheritence depth")