Analysts attribute some of the recent share price declines to sales by investors anxious that trade tensions will hurt growth, while trade tariffs and rising interest rates raise costs for businesses.
Concerns about higher rates have roiled the U.S. Treasury market, where yields have risen to multi-year highs. Rates on many types of loans, such as those for mortgages and cars, tend to be tied to the government bond.
Tech and luxury stocks have been among those to feel the worst pain in the sell-off.
"The -4.2 percent drop in the S&P 500 over the past five days has been triggered in part by fears over corporate earnings as trade uncertainties, rising input costs and higher interest costs start to bite", said economist Louis Gave of Gavekal Research in a report. Meanwhile safe bets, such as utilities and consumer staples, were the only positive notes in the sell-off.
"Clearly stocks are spooked by higher rates and maybe some inflation that seems to be creeping in", said Michael Farr, CEO of Farr, Miller & Washington. A dip in equities may even take the edge off asset values some Fed officials worry have been "stretched" compared to historic levels.
"It's all about investors rethinking their exposure to stocks."Many of the biggest U.S. names fell hard in Wednesday's session, with Apple, Boeing and Facebook all slumping more than four percent and Amazon, Nike and Microsoft shedding more than five percent". The S&P 500 sank 2.3 percent, marking its sixth day of decline.
"The markets are bringing up their expectations for growth, and have been bringing them up all year", Perli said. He expects US economic growth will have "fallen significantly" by mid-2019, causing the USA benchmark index to retreat by about 15 per cent from it's recent peak.
F-35 jets: U.S. military grounds entire fleet
Mission capable rates now hover between 49 and 71 percent, according to Defense News , which first reported the order. The British Ministry of Defence announced on Thursday that the British military had not grounded their F-35 jets.
In Asia stock markets braced themselves for another day of losses.
Mnuchin's calm was echoed by Federal Reserve officials and other worldwide policy makers as the fall in US equities extended to Asia on Thursday.
"Later, White House Press Secretary Sarah Sanders said the fundamentals and the future of the United States economy remain incredibly strong".
The 10-year yield is now 3.20 percent, the highest in than seven years and up sharply form 2.82 percent in late August. The current benchmark interest rate is 2 to 2.25 percent. It was at just 3.05 percent early last week.
Wednesday President Trump went further and knocked the Federal Reserve for continuing to raise interest rates despite some recent market turbulence.
Trump blamed the Federal Reserve - and his appointee Powell - for the big drop Wednesday.
"I think the Fed is making a mistake", Trump said to reporters after landing in Erie, Pennsylvania, for a campaign rally on Wednesday. "The Fed has gone insane". "I think what they're doing is wrong", Trump said. "The Fed will stay on a measured pace".
"This is just who we are and I think who we will always be, which is, we're a group who - we're quite removed from the political process", Powell said in a recent interview.
Overnight, Chinese stocks fell 5 percent while South Korean and Japanese stocks lost around 4 percent.