It can tell how much you have to eat through to breakthrough. Volume by Priice tells you how many shares changed hands at a price. That bar graph tells you that ELTP traded alot aroudn .18. The theory is that those buyers at that price--if they are still around and held--will sell when they get back to break even.
Psychological.
Just another variable--and another one that prompted me to sell before the news. I saw the lid at .18, so getting out .015 cheaper was not leaving much on the table.
It is not a perfect variable--just one of many to take into account.
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