Showing normalized histograms
To report the histogram as a percentage of a whole, the histogram count is normalized to add up to 1, and then the bars represent the proportionate frequency.
To normalize a histogram, click Settings in the VISUAL menu, open the Basic section, and select the Normalized histogram option.
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The following image shows the two versions of the histogram. You can see that the change appears in the vertical axis and the tooltip, where frequency is reported as a number of incidents on the upper graph, and as a percentage on the lower graph.
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