This visualization uses a scatterplot to show GDP changes for the USA and Germany after World War II, with the y-axis reporting GDP in percent and the x-axis showing the year. A categorical color scale distinguishes the two countries, and an interactive color legend filters the data by country on click. The code loads data from the IMF via D3’s `csv` function and builds the chart using `scaleLinear`, `axisLeft`, `axisBottom`, and `scaleOrdinal` with `schemeSet2`. The update pattern follows Nick Lima’s approach for handling selections and transitions in SVG.