You may be surprised to see that a very small segment of the U.S. population voted for either Trump or Clinton in the primaries. In this marimekko, you can see that only 60M Americans voted in the primaries and only 5% of the U.S. population chose Clinton and 4% chose Trump.
The default calculation for segment value percentages is the percent of the bar total. To show the segment value percentages as a percent of the total population, I added a row in the Mekko Graphics Data Editor with the grand total value of 324M in each column. Then, in the Format Chart task pane under the Values tab, I selected that row to be the 100% calculation for the chart.
You can download this chart using SlideShare: