This example shows monthly counts of a categorical status variable from September 2017 through September 2019, rendered as a smooth area chart. A main focus panel displays the full time series, while a smaller context panel beneath it provides a brush for selecting date ranges. Users can also pan and zoom directly on the focus chart. The visualization uses D3 v4 with `d3.brushX`, `d3.zoom`, and `d3.area` with monotone curve interpolation, reading data from a CSV file where dates are parsed with `d3.timeParse`.