Choose Between a Bar Chart and Pie Chart

What are bar charts and pie charts?

Bar chart: Bar chart depicts numerical values against distinct categories in a two-axis plot.On one axis, the category levels are listed.

Pie chart shows how some total amount is divided among distinct categories as a circle (the namesake pie) divided into radial slices.

• Bar charts are used when one variable is categorical and one is numeric, e.g. marital status (3 categories) and age
• Stacked bar charts (or simply stacked charts) are used when there are more than one categorical variables, e.g. marital status and gender plotted in two different colours
• Line charts are also used with one categorical variable and one numeric variable
• If time is a variable to be plotted, it almost always plotted on the x-axis of a line chart
• Pie charts have poor readability and thus you should avoid using them
• Scatter plots are used when you want to plot two numeric variables e.g. age and income
• You can add transparency in scatter plots to improve readability