This visualization plots US permanent visa applications by education level and year of degree, using a circular mark for each application record. It encodes the count of applications through circle size, while positioning education level on the y-axis and degree year on the x-axis. The code leverages the vega-lite-api with d3.csv to load data from a GitHub gist, and configures axes, tooltips, and a dark color scheme via vega-tooltip and vega-lite’s configuration object.