Amazon stock plunged 8% in premarket trades Friday. The e-commerce giant reported second-quarter results that topped Wall Street's expectations, but gave a mixed outlook. For the current quarter, Amazon predicted sales of $176.75 billion at the midpoint of its range, compared with analyst expectations for $173.27 billion.

Markets are assessing the reshaped US trade landscape after Trump on Thursday laid out steep new tariffs for dozens of countries.

Stocks slumped and Treasury yields fell sharply Friday (August 1) after a weak report on hiring and the latest gyrations in US trade policy shook Wall Street. The S&P 500 fell 1.8% and is on track for its biggest decline since late April.