This example shows a line chart of population values from 2005 to 2015, drawn as an SVG path using D3 v4’s `d3.line` and `d3.scaleTime`/`d3.scaleLinear` scales. The data is loaded from `data.json` with `d3.json` and parsed via `d3.timeParse`. A hover interaction uses a transparent overlay rectangle, `d3.mouse`, and `d3.bisector` to find the nearest year, then updates a focus circle, dashed hover lines, and a value label via direct SVG attribute manipulation. The y-axis labels are formatted in thousands with a custom tick format.