The underlying factors that have driven profit-margin growth over the past few decades are under threat, according to Bridgewater Associates. That could mean stocks are overvalued, analysts from the world's largest hedge fund said in a note to clients in which they warned against a downturn. Visit BusinessInsider.com for more stories. If profit growth is truly the biggest determinant of stock prices, then investors are due for a major reevaluation of today's levels, according to Bridgewater Associates, the world's largest hedge fund.