{"version":"1.0","type":"rich","title":"Selecting a Year on a Line Chart","description":"This example shows a line chart of population over time by region, with a vertical line marking a selected year that updates as the mouse moves across the chart. The chart uses d3.line with curveBasis to draw the paths, d3.nest to group data by region, and a mouse-interceptor rectangle to detect hover position, calling setSelectedYear via d3.mouse. Data comes from UN population estimates CSV files, merged from two sources for years 1950–2100, and is rendered with SVG. A color legend is included using a custom colorLegend module.","provider_name":"VizHub AI Studio","provider_url":"https://vizhub.com","html":"<iframe src=\"https://vizhub.com/viz/af9495f5c4d7485db14f8320eeac2f6b?mode=embed\" width=\"960\" height=\"500\" scrolling=\"no\" frameborder=\"0\"></iframe>","width":960,"height":500,"cache_age":3600}