COMPONENTS

Bar Charts

A bar chart is used to compare values by category and displays the values using horizontal bars. One axis displays the categories while the other axis displays a scale of values or numerical metrics.

Bar Chart
Paired Bar Chart
Stacked Bar Chart
Stacked Bar 100% Chart

DO

  • The height of the bars should be taller than the space between the bars.
  • Label your axes and include the units for the x-axis.
  • On x-axis, choose increments that are easy to follow.
  • Display negative values left of the zero baseline.
  • Always include a zero baseline on the x-axis. A bar graph that doesn't include a zero baseline is misleading.
  • The zero baseline should be thicker than the rest of the grid lines.
  • The legend is the key to the information. It should be positioned above or to the left of the chart and in the same order as the sequence of the bars.

DON'T

  • Don't truncate the bars or a single bar. Truncation misrepresents the actual value of each column.
  • Don't position the key below the chart.
  • Don't use shadows on the bars. They can be distracting and misleading.
  • Don't use 3-D bars. They are misleading because it is hard for the viewer to determine the width of the bar.