How I Made That: Interactive Heatmap
Add interaction so that you can show different segments of the data and allow comparisons.

In its simplest form, a heatmap is a grid of cells that you color based on data. An interactive version can help you compare categories, groups, or in this example, time segments.
To compare male and female income in American households, I used a heatmap that looked like this:
A click of the button lets you compare the distribution of income in the household in 1970 against 2015. Try it out here.
In this walk-through, I’ll show you a simplified version of the interactive and describe how you can apply this to your own data.
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