Tuesday's was the S&P's worst drop since August 24.
Monday's drop followed an 8.5 per cent slump in Chinese markets.
Passwords, addresses, photos, medical data all at risk
Cyber espionage operations dated back to at least 2005
Apple's stock market value rose beyond $700 billion.
The chipmaker also promised to hire more women
The president's moves will make it easier for entrepreneurs to work in the United States
Ellison and the two new co-CEOs each stressed that nothing would change under the new management structure, with Ellison staying on as executive chairman and chief technology officer.
Users seem to like the idea too: in a recent survey by technology consultancy IHS, 83 per cent were interested in wireless charging; in China, the figure was 91 per cent.
Apple Inc's embrace of wireless charging for its new Watch may be a defining moment for a technology that's languished for years amid competing standards and consumer confusion.
Has Steve Jobs' handpicked successor inherited the magic touch or is Apple's winning streak coming to an end?
The chipmaker's Clover Trail+ mobile chip will be used in one version of its 10.1-inch tablet.
The move puts it in competition with Apple, Amazon and Google.