Jones connects this directly to your portfolio. The current S&P 500 price-to-earnings (PE) ratio of 22, he told the podcast, is a level that has historically implied negative 10-year forward returns — which means investors buying the index today, on average, have historically ended up with less money a decade later than they started with, according to data (5).Tax revenues, consumer spending, and corporate investment decisions now increasingly depend on whether stock prices stay high. The U.S. has never bee ...