{"version":"1.0","type":"rich","title":"Melting Data for Multiple Lines","description":"This visualization displays regional population changes over time as multiple colored lines, with a vertical marker indicating the currently selected year. Users hover over the chart to update the selection, and a legend identifies each region. Built with D3 v5, it uses `nest` to group data by region and `scaleOrdinal` for colors, rendering with SVG. The data is sourced from UN population estimates, melted into tidy format for the line chart.","provider_name":"VizHub AI Studio","provider_url":"https://vizhub.com","html":"<iframe src=\"https://vizhub.com/viz/9cf74731013240b8b20b74f5ad2453f7?mode=embed\" width=\"960\" height=\"500\" scrolling=\"no\" frameborder=\"0\"></iframe>","width":960,"height":500,"cache_age":3600}