This example shows monthly stock prices for Microsoft, Amazon, and IBM from 2000 to 2010 as animated, stacked area charts. Each symbol is rendered in its own horizontal band, with a dark line tracing the price over time. The code uses d3.csv to load data, d3.nest to group by symbol, and d3.svg.area and d3.svg.line with basis interpolation to draw the shapes. A d3.timer drives the sequential reveal of data points, while d3.layout.stack computes the stacked offsets.