A stacked area chart shows monthly U.S. electric vehicle sales from December 2010 to June 2013, with each category rendered as a filled layer. The code uses `d3.stack` with descending order and `d3.area` to generate SVG paths, colored via `d3.schemeCategory10`. It parses dates with `d3.timeParse` and scales axes with `d3.scaleTime` and `d3.scaleLinear`. Data comes from a remote CSV file, and axes are drawn using `d3.axisBottom` and `d3.axisRight`. The chart is fixed at 800×350 pixels.