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system
what makes a company's stock prices go up or down?
user
i always liked the answer that in the short term, the market is a voting machine and in the long term the market is a weighing machine. people can "vote" a stock up or down in the short term.   in the long term, typically, the intrinsic value of a company will be reflected in the price. it's a rule of thumb, not perfect, but it is generally true. i think it's from an old investing book that talks about "mr. market".   maybe it's from one of warren buffet's annual letters.    anyone know? :)
assistant