If you are having a tough time deciding whether to dump a stock you own, don’t despair. You aren’t alone. In investing, nothing is harder. Nothing.
Some people offer a simple formula — such as, always sell a stock if it has dropped 20 percent or if it has risen 100 percent or if its price-to-earnings ratio (P/E) gets above 30. Sorry, but my views are a little more complex. Here are my guidelines: