This line graph shows the number of Walmart employees in millions from 2009 to 2022, based on an employees.csv dataset. Interactive hover selection highlights the nearest data point, displaying its exact value as a label and drawing a red vertical rule at that year. Built with Vega-Lite's API through `vl.markLine`, `vl.markCircle`, and `vl.markRule`, it uses `vl.selectSingle` for mouseover interactions and configures axis styling via a custom config.js.