Emerging markets can expect some turbulence next month after US Fed chair Janet Yellen left the door open for a rate hike as early as 21 September. In closely watched remarks at the Fed’s annual Jackson Hole monetary policy conference, Yellen said “a lot of new jobs were being created and economic growth would likely continue at a moderate pace. ‘I believe the case for an increase in the federal funds rate has strengthened in recent months,’ she said.” US shares headed lower on Yellen’s remarks, while the USD surged in Friday trading, Reuters noted. An interesting analysis piece from Reuters suggested Yellen has no intention of trying out negative rates or helicopter money, although the WSJ (paywall) says she noted that additional quantitative easing is on the table. CNBC, the Financial Times and all have solid coverage, depending on your preferences this morning.

More doom and gloom for you to start the workweek: US economic growth was revised downward to 1.1% in the second quarter, “underscoring a weak performance in the first half of 2016,” the Financial Times (paywall) reports. This comes as the salmon-colored paper warns that “the rally in emerging markets masks frailties,” warning that “investors should be wary of Chinese debt lurking in a jumble of assets.”

Wait, it gets worse: Index funds are “eating the world,” the Wall Street Journal warns. It’s a nicely alarmist headline picks up on a research report headlined “The Silent Road to Serfdom: Why Passive Investing Is Worse than Marxism” — and the fact that in the past year, USD 310 mn in capital has fled actively managed portfolios, and USD 409 bn has flowed into index funds — to argue that “autopilot portfolios could become so popular that they distort the financial markets.” The research note that kicked off the discussion is getting plenty of ink — everywhere from CNBC and Barron’s to Bloomberg and (wait for it) Reddit.