The U.S. stock market's break in its recent rally left investors wondering last week if they're seeing a turning point or just a blip in the upward path.
This week could make it harder to figure out, considering that the long Memorial Day weekend typically signals the start of the summer. The U.S. stock market was closed on Monday for the holiday.
The three major U.S. stock indexes posted a decline for the week on Friday, their first weekly loss since mid-April, raising some fresh worries that this year's rally may be weakening.
Among investors' biggest concerns right now is how soon the Federal Reserve may be ending its stimulus program. The minutes released this week from the Federal Reserve's latest meeting showed some officials were open to tapering large-scale asset purchases as early as at the June meeting.
Volume picked up sharply in the last two days following the release of the Fed's minutes on Wednesday.
"We should have already been prepared for" the Fed's eventual tapering of stimulus measures, said Bryant Evans, investment adviser and portfolio manager at Cozad Asset Management, in Champaign, Illinois.
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"The market is perhaps just looking for an excuse to sell off some gains. And then you throw in the 'sell in May and go away' philosophy, well, here we are (at) Memorial Day weekend."
The pickup in volume suggested to some a shift in sentiment, though activity has been below average throughout the rally, which has taken the Dow and the S&P 500 to record highs.
Much of that rally has been driven by the Fed's continued economic stimulus.
The rally's duration and scope have surprised even veteran market watchers, many of whom have been expecting a reversal in the trend for several weeks.
The market has managed to avoid any significant pullback since November, and dips have been used as buying opportunities. Even with the week's 1.1 percent loss, the S&P 500 remains up 15.7 percent for the year.
Volatility has also not been a problem.