Sasini always reminds me of Mr. Market parable in the Intelligent Investor
"Imagine that in some private business you own a small share that cost you $1,000/-. One of your partners Mr. Market is very obliging indeed. Everyday he tell you what he thinks your interest is worth and furthermore offers to either buy you out or sell you an additional interest on that basis. Sometimes his idea of value appears plausible and justified by business developments and prospects as you know them. Often, on the other hand, Mr. Market lets his enthusiasm or his fears run away with him, and the value he proposes seems to you a little short of silly.
If you are a prudent investor or a sensible businessman, will you let Mr. Market daily communication determine your view of a $ 1,000 interest in the enterprise? Only in case you agree with him, or in case you want to trade with him. You may be happy to sell out to him when he quotes a ridiculously high price, and equally happy to buy from him when his price is low. But the rest of the time you will be wiser to form your own ideas of the value of your holdings, based on full reports from the company about its operations and financial position."