Iginla2011

I'm inclined to disagree with bannisja's answer because im sure it's based purely on the volume traded and price doesn't come into it(correct me if i'm wrong but I haven't seen any examples that take price into account).

I think it's because VWAP attempts to predict the trading volume for the day rather use the actual trading volume. A percentage of trading volume strategy would take into account the trading volume for the day.