How do I create a stacked bar chart in R with ggplot2?

Use geom_bar(position = "stack") from the ggplot2 package. Variables needed: 2 categorical + 1 numerical.

What data types work with a stacked bar chart?

A stacked bar chart works best with categorical, numerical data. It requires 2 categorical + 1 numerical.

CompositionComparison CategoricalNumerical

Stacked Bar Chart

ggplot2: geom_bar(position = "stack") · Package: ggplot2 · Variables: 2 categorical + 1 numerical

WHAT IS A STACKED BAR CHART?

A stacked bar chart divides each bar into colored segments representing sub-groups, showing both the total value and its composition at once. It answers questions like "what is the total per category, and how is that total broken down?" For example, total revenue per quarter broken down by product line, or total headcount per department by seniority level. Stacked bars work best with 2-5 segments. For more segments, consider a treemap. In ggplot2, use geom_bar(position = "stack") with a fill aesthetic.

BEST FOR

· Part-to-whole within categories
· Total and breakdown simultaneously
· 2-5 segments per bar

AVOID WHEN

· Comparing individual sub-group values across categories
· More than 6 segments

R + GGPLOT2 CODE EXAMPLE

ggplot2

ggplot(mtcars, aes(x = factor(cyl), fill = factor(gear))) +
  geom_bar(position = "stack") +
  labs(title = "Gears within Cylinder Groups", fill = "Gears")