COMPONENTS

Bar Chart

Ideal for displaying values by category. The width of the bar is proportional to the value it represents.

chart-type-bar

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.