Interest rates on long maturity U.S. Treasury bonds fell again Monday, touching the lowest levels since 2017. The 10-year Treasury bond yield dropped under 2.4% as the German 10-year bond yield fell into negative territory.
Investors are concerned about global growth, Brexit, and the situations in Venezuela and Israel.
Global stocks also gave up some ground, adding onto the big losses from last Friday.
Investors are still digesting weak U.S. factory data last week that prompted an inversion of the U.S. Treasury yield curve, which is widely seen as an indicator of an economic recession.
Apple shares fell 1.2%, weighing on indexes, as the company on Monday unveiled a streaming video service.