It's worth noting that although the points drops have been large, fear-mongering in some quarters is being reigned in slightly by the fact that in percentage terms, we aren't into the territory seen in previous market crashes, although still significant. Facebook lost 5.4 percent. Intel, due to report earnings later this week, fell 4.7 percent. The Dow opened up in the morning.
The S&P 500 fell 33 points, or 1.2 percent, to 2,706 as of 11:35 a.m. The Dow is looking at its worst month in eight years.
The benchmark S&P/ASX200 index was down 164.9 points, or 2.83 per cent, at 5664.1 points at 1615 AEDT on Thursday, while the broader All Ordinaries was down 2.82 per cent.
"That's been driving a good bit of the move in the 10-year lately, expectations about how many rate increases there are going to be in 2019", Martin said. "This drop is coming out of technology".
The dive in formerly high-flying USA tech stocks sent investors scampering to the safety of sovereign bonds, with yields in 10-year Treasuries US10YT=RR falling the most since May to 3.11 percent.
Wednesday's market rout was triggered by concern over tariffs, China's slowdown on corporate profits, rising costs, bond yields, Italy's budget, and the upcoming US mid-term elections.
The absence of a tax-cut boost and the likelihood of higher interest rates, which can raise borrowing costs for businesses, are also giving investors reasons to worry that company earnings growth will slow.
Most economists expect ECB President Mario Draghi to say the bank will stick to plans to end stimulus this year. "It turned out he's not".
Volatility in US markets has weighed on Asia for some time as trade tensions between the USA and China heighten. "I've recently been describing them as akin to driving a auto with one foot pushing hard on the accelerator while the other is tapping on the brakes".
Energy stocks fell 3.50 percent, the most among the sectors, as oil prices plunged after Saudi Arabia said it could supply more crude quickly if needed, easing concerns ahead of US sanctions on Iran. The semiconductor industry also has shown weakness.
The U.S. economy could begin to slow within "no more than a few quarters", Capital Economics predicted in a research note. Earnings reports from Q3 are arriving, and many companies have beat their estimates.
"Right now markets are still trying to reprice", said Chris Zaccarelli, chief investment officer at the Independent Advisor Alliance.
Some of those buyers are the companies themselves.
Australia's S&P/ASX 200 Index also fell more than 2%. The Dow dropped almost 500 points Tuesday before climbing back in the afternoon. The average was briefly down more than 540 points. Four sectors were particularly hard hit, it said, with declines of at least 20 percent: material, financial, consumer discretionary and industrial stocks.
"After the elections, the buybacks will be allowed and kick in", she said.
According to data analyzed by Reuters, the proportion of stocks, regions and sectors that are technically in a bear market has shot up since the start of January, prompting some analysts to conclude the bull run may already be over.