Rob Arnott, founder and CEO of Research Affiliates, says investors should “avoid U.S. stocks and buy emerging market equities to outperform in the coming years,” according to a recent CNBC interview.

Arnott was a pioneer in developing indexing strategies that weight portfolio holdings according to valuation measures rather than market capitalization (a strategy typically used by passive index funds) and therefore overweights undervalued companies and underweights overvalued companies. The article cites data on the Research Affiliates website showing that approximately $179 billion of assets are managed using these strategies as of March 2017.

According to Arnott, the U.S. market P/E of 29 is very worrisome. “The markets have been higher than those levels twice in history,” says Arnott, “the tech bubble and 1929. That’s not very pleasant company to keep. I’d be very worried about U.S. equities.”

The P/E in the European markets of around 14, Arnott argues, is “not bad,” and emerging markets, at around 11 times earnings, is “cheap.” He refers to emerging market stocks as the “low hanging fruit in world investing today.”