This interactive area chart displays car registrations in Austin, Texas from 2012 to 2021, with a red rule marking the hovered fiscal year and text labels showing exact car counts. Built using Vega-Lite API and D3.js, the visualization layers an area mark with circles, applying a single selection on x-encoding with mouseover events to highlight the nearest data point. Data is loaded asynchronously from a GitHub-hosted CSV file using D3’s csv parser, and the chart is rendered as SVG with tooltip support. The configuration customizes axis styles and label colors for readability.