This interactive area chart visualizes total billing amounts by month, segmented by year, based on a student information dataset. The visualization uses Vega-Lite API to render smooth, semi-transparent areas with white borders for each year, allowing comparison of spending patterns over time. The code filters the CSV data to include only active statuses with billing amounts between zero and 3000, while converting negative discount values to positive. A tooltip displays month names, billing totals, and years, with the visualization resizing to fit the browser window.