Sankey Timeline

I created this visualization for a voting rights non-profit still in stealth mode. This scrollable timeline shows small changes in voting status among members of a much larger population. The status transitions from one date to the next are shown by mini-Sankey diagrams, with the width of each path scaled to the number of people in that transition. Since the relative volumes can be several orders of magnitude, you can choose either the normal scale to show the actual (small!) numbers, the log scale to magnify the changes, or a square root scale for a Goldilocks medium.

The timestamps in these data are not regular intervals, but this chart would work as well with any regular interval, or even rolled-up selectable intervals.

Example data via client API, obfuscated for IP protection. Visualization via D3js.