This visualization uses a streamgraph to display median house sale prices over time, broken down by property type and number of bedrooms. A dropdown menu allows the user to select which stream is sorted at the top of the graph. The stacked areas are rendered as SVG paths using `d3.area` with a `stackOffsetSilhouette` layout, and the x-axis encodes time as years with seasonal divisions. Hovering over a stream reveals a tooltip with the price for that date, calculated from the stack’s bounds. The data comes from a CSV file (`ma_lga_12345.csv`) listing sale dates and median prices.