Price per share is based on MANY different functions: expectations; earnings; revenues; shares available to the public (float); but it all comes down to supply and demand.
More buyers of the stock...price goes up. More sellers of the stock...price goes down.
The above mentioned criteria ONLY function to drive buyers and sellers....which affect the price of the stock.
Sometimes good news will bring a drop in price because people NEED to sell for whatever reasons. And you without a doubt have seen this to be true.
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