If I understand what goes on behind the scenes, the prices used for a security are not the historical prices but have been adjusted for certain corporate actions such as splits. So let's say a stock on day x was trading at $100/share and split 2 for 1 so that on day x+1 it started trading at$50. The price on day x is adjusted to \$50. That all makes sense. Here's my question (finally): Is the volume adjusted?