{"version":"1.0","type":"rich","title":"Melting Data for Multiple Lines","description":"This visualization shows population over time by region, with multiple colored lines tracing each region’s trajectory from 1950 to 2100. The chart uses a time scale for the x-axis, a linear scale for population, and an ordinal color scale with a custom legend. D3’s `nest()` and `scaleOrdinal` group and color the series, while `d3.line` with `curveBasis` smooths the paths. Data comes from UN population estimates and medium-variant projections, melted into a tidy format for plotting as SVG.","provider_name":"VizHub AI Studio","provider_url":"https://vizhub.com","html":"<iframe src=\"https://vizhub.com/viz/dcd82f95c2514b15be2d75cc21fdd392?mode=embed\" width=\"960\" height=\"500\" scrolling=\"no\" frameborder=\"0\"></iframe>","width":960,"height":500,"cache_age":3600}