Example of a streamgraph that can be divided into multiple area charts.
Modified http://d3js.org/d3.v3.min.js to a secure url
Modified http://raw.github.com/mbostock/d3/master/lib/colorbrewer/colorbrewer.js to a secure url
https://d3js.org/d3.v3.min.js
https://raw.github.com/mbostock/d3/master/lib/colorbrewer/colorbrewer.js