Using Percent Scales and Accumulating Y Across X
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Show Y as Percent

You can use a percent scale on the y-axis. The percent scale can relate to the total of all categories, or, if you have clusters, the total of a cluster grouping.  

For example, the following graphs show the effects of smoking (1=Smokes, 2=Nonsmoker), exercise (1=Ran, 2=Still), and sex (1=Male, 2=Female) on pulse rate.

 

If you choose Across all categories, all of the bars in the graph total 100%.

If you choose Within categories at level 1 (outermost), all of the bars for Smokes=1 total 100%, and all the bars for Smokes=2 total 100%.

If you choose Within categories at level 2, the bars for the four Smokes by Ran combinations each total 100%.

Note

You cannot calculate percent within the innermost level.

Accumulate Y across X

You can use a cumulative frequency scale on the y-axis. When you choose this option, the height of a bar is the sum of the y-value of that bar plus the y-value of the bars to the left of it. Accumulating y across x can be the total of all categories, or, if you have clusters, to the total of a cluster group.  

For example, the following graphs show the effects of smoking (1=Smokes, 2=Nonsmoker), exercise (1=Ran, 2=Still), and sex (1=Male, 2=Female) on pulse rate.

 

If you choose Across all categories, all of the bars in the graph accumulate from left to right.

If you choose Within categories at level 1 (outermost), all of the bars for Smokes=1 accumulate left to right, and all the bars for Smokes=2 accumulate from left to right.

If you choose Within categories at level 2, the bars for the four Smokes by Ran combinations each accumulate from left to right.

Show Y as Percent in Combination With Accumulate Y across X

You can also use these two options together. In this case, percentages are cumulative.

For example, the following graphs show the example with both options:

 

If you choose Across all categories, all of the bars accumulate  percentages from left to right.

If you choose Within categories at level 1 (outermost), all of the percents for Smokes=1 accumulate from left to right, and all the percent for Smokes=2 accumulate from left to right. The percents are also accumulative, so that the final bar in the grouping is always 100%.  

If you choose Within categories at level 2, the bars for the four Smokes by Ran combinations each  accumulate percents from left to right.