For the week, the S&P 500 dropped 2 percent, while the Dow was down 3 percent and the Nasdaq fell 1 percent. Heavy equipment maker Caterpillar, health giant UnitedHealth and industrial conglomerate General Electric were the big drags.
Dow futures are down 194 points, the index having closed 420 points lower yesterday, while S&P 500 futures are trading over 13 points lower. Analysts and traders have cautioned that much of the turbulence this week may stem from market positioning as much as a substantial change of tack by Powell.
Like-for-like sales, a key measure of a retailer's fortunes, were down 3.7% year-on-year in the 14 weeks to February 3; analysts had expected a decline of 2.4%.
Best Buy jumped around 5 percent after it reported strong same-store sales for the fourth quarter, recovering from falls overnight due to the USA consumer electronics retailer's announcement of 250 small mobile phone store closures. The yield on the 10-year Treasury note sank to 2.81 percent from 2.86 percent late Wednesday.
"These are the dangers", said said Donald Selkin, New York-based chief market strategist at Newbridge Securities Corp.
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New York Federal Reserve President William Dudley also added to the evidence that the USA central bank under new chief Jerome Powell would seek to tighten monetary policy with four interest rates rises this year, more than previously expected. Later in the week, though, Powell may have calmed some of the fears when he said that he does not see inflation in wages "at a point of acceleration".
Worries about potentially higher rates and inflation have reintroduced markets to volatility following their unusually calm run in 2017 and early this year. February represented the biggest one-month percentage decline for the Dow and the S&P since January 2016, and it ended a 10-month streak of gains for both. Crude oil was again decidedly negative in the session. Brent crude, the global standard, lost 90 cents to $63.83 a barrel. The Nasdaq composite lost 127 points, or 1.8 per cent, to 7,145.
In Europe, France's CAC 40 lost 2.4 per cent, and Germany's DAX fell 2.3 per cent.
Coming after the 0.4% fall in the ASX 200 in February, Thursday's 0.7% fall, March is already looking as though it will be in the red by more than 1.5% after just two days trading. The FTSE 100 in London gave up 1.5 per cent.
Gold rose $18.20 to settle at $1,323.40 per ounce.