Motivation What’s Google Charts/googleVis? Example 1: US Immigration Data, 2015 Example 2: Longitudinal Study Progression Pros, Cons and Other Options Session Details Photo: American political parties over time, taken at the National Museum of American History, August 2017 This post was originally written in January 2017, and slightly updated January 2018 Motivation To visualize the progression of patients over the course of a longitudinal study, I wanted to do a Sankey plot.