A Week in the Life of the Economy

For all the recent talk about recovery, the economy’s vulnerability was on full — at times stomach-dropping — display this week.

Origin of Wall Street’s Plunge Is Still Unclear to Regulators

Officials from federal agencies hunted for clues amid a tangle of electronic trading records to find out what caused Thursday’s near panic on Wall Street.

The plunge protection team had to wake up. This is not the last time.