What to do
A double bar graph compares two related data sets across the same categories. Each category has two bars, usually shown side by side, so you can compare the values directly.
Step-by-step method
- Read the category names carefully. These are the labels along the horizontal axis.
- Identify the two data sets you need to display. Keep them separate so you do not mix the values.
- Choose a scale for the vertical axis that fits the largest number in the data.
- Draw two bars for each category. Make sure both bars start from the same baseline and use the same scale.
- Use different colors, shading, or patterns for the two groups, and add a legend if needed.
- Label the graph clearly with a title and axis labels.
Check your work
- Each category should have exactly two bars.
- The heights of the bars should match the data values.
- The scale should be consistent across the whole graph.
- The graph should make comparison easy and accurate.
Common mistake to avoid
Do not use different scales for the two bar sets. That makes comparisons misleading.
Final check
When you finish, compare your drawn bars to the given data one more time to make sure every value is shown correctly.