Volume tells you the number of shares or contracts traded during a day. Volume is an indicator of demand for the stock. Obviously, you can get a jump in volume that is due to only a handful of people buying large amounts of shares (whales).
A large volume day I am looking for will have buys in the 100,000 - 500,000 shares during 1 transaction. If we have a lot of those transaction in 1 day it will show a definite increase in demand which will start to influence the PPS. Typically this will show new investors coming in, or current investors increasing their position.
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