{"version":"1.0","type":"rich","title":"Selecting a year on a line chart","description":"This visualization shows global population trends by region from 1950 to 2100 as a multi-line chart. Users can hover over the chart to select a specific year, which triggers a vertical guide line and updates the highlighted data point. The implementation uses D3 v5 with SVG rendering, leveraging `d3.nest` for data aggregation and `d3.scaleTime` for the time axis. Population data comes from UN estimates and medium-variant projections, processed through a custom melt function, while the interactive year selection relies on mouse events and `d3.mouse` positioning.","provider_name":"VizHub AI Studio","provider_url":"https://vizhub.com","html":"<iframe src=\"https://vizhub.com/viz/8157f9a810ce4884ad52b2e472541300?mode=embed\" width=\"960\" height=\"500\" scrolling=\"no\" frameborder=\"0\"></iframe>","width":960,"height":500,"cache_age":3600}