Retirees and investors near retirement are in a tough spot. They need growth from their stock market portfolio to fight inflation and rising health care costs, but another major market drop could leave stocks in a "lost period" which they don't have the time to wait out. As a general rule in the current investment era, many financial firms tell recent retirees to keep more than half of their portfolio in stocks and then dial it down as they get older. Once upon a time, a 65 year-old with 50% in stocks would ...