An interactive line chart displays a selected economic indicator—GDP, CPI, life expectancy, or tax revenue—across an indexed x-axis. Users choose an indicator via a dropdown menu, triggering a brushless update that rescales axes and redraws the steelblue line path. Built with React and D3 v7, it loads CSV data from a GitHub repository and renders interactive SVG elements using d3.csv, d3.scaleLinear, d3.line, and d3.axisBottom/Left.