About bar charts
A bar chart typically displays data values as a set of vertical bars, but you can transpose the axis to display horizontal bars. When you view report data in a chart with vertical bars, you can easily compare the values. A bar chart is useful to show data changes from one time period to another, for example from one year, or quarter to another, or to illustrate comparisons among items.
Standard bar charts are side-by-side but you can have stacked and percent stacked bar charts that also show the relationship of individual items to a whole.

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