File:SparqlCharts Stacked Area Chart streamed.png
Screenshot taken from nvd3.org, showing the "stacked-area chart" format, that can be used in the SparqlCharts extension. This format makes use of D3.js and NVD3. D3.js is a JavaScript library distributed under the BSD 3-Clause License. NVD3 provides re-usable charts and chart components for D3.js and is distributed under the Apache License, Version 2.0, see here.