U.S. stocks on Monday declined for a third session, pulling the S&P 500 into the red for the year, as investors shed high-profile assets that fared well in 2013 in search of better values.
"Investors are moving out of many areas of the market that performed well last year. In particular, the Internet, social media and biotechnology industries are experiencing some notable weakness," Russ Koesterich, BlackRock's global chief investment strategist, wrote in afternoon commentary.
"The momentum meltdown continues to be the story," said Art Hogan, chief market strategist at Wunderelich Securities, referring to the bashing of Internet names, which on Monday included Amazon.com, Priceline Group, Google and Apple.
(Read More: Stocks may be challenged by momentum drop as earnings start.)
"Investors are rotating out of the higher beta stocks, if you will, to utilities and other quote, unquote, safe stocks," said Paul Nolte, senior vice president, portfolio manager at Kingsview Asset Management.
"Those things that did poorly last year are doing fine; those things that did fine last year are doing poorly. I don't read anything more into it than a rotation into safer areas," Nolte added.
The unofficial start of the quarterly earnings season begins after Tuesday's close, with aluminum producer Alcoa slated to release earnings. Banks JPMorgan Chase and Wells Fargo also report this week, along with retailer Bed, Bath & Beyond.
"In recent weeks a near-record number of S&P 500 firms have issued negative guidance with some blaming the weather and some blaming the strong dollar," David Kelly, chief global strategist at J.P. Morgan Funds, wrote in emailed research.
"However, the correlation between guidance and results does not appear stable," Kelly added.
Major U.S. Indexes
After hitting record highs late last week, the Dow Jones Industrial Average on Monday dropped 166.84 points, or 1 percent, to 16,245.87, with Pfizer leading blue-chip declines that included 23 of its 30 components.
Pfizer fell after its experimental breast cancer drug yielded positive results in a clinical trial, but researchers found overall survival to be statistically insignificant.
The shed 20.05 points, or 1.1 percent, to 1,845.04, with TripAdvisor leading a retreat in the consumer discretionary sector. Consumer staples fared best among the S&P 500's 10 major industry groups.
Shares of Kellogg rallied on speculation the cereal maker could be an acquisition target.
The Nasdaq fell 47.97 points, or 1.2 percent, to 4,079.75, with the technology-heavy index recording its biggest three-session drop since November 2011.
The Dow and S&P 500 posted their worst three-day losing streaks since Jan. 27, 2014.
The CBOE Volatility Index, a measure of investor uncertainty, rose 11 percent to 15.53.
On the New York Mercantile Exchange, crude-oil futures for May delivery fell 70 cents, or 0.7 percent, to $100.44 a barrel. Gold futures for June delivery dropped $5.20, or 0.4 percent, to $1,298.30 an ounce.
The U.S. dollar declined against the currencies of major U.S. trading partners and the yield on the 10-year Treasury note used in figuring mortgage rates and other consumer loans fell 3 basis points to 2.695 percent.
On Friday, stocks closed the week with a large thud, with the Dow and S&P 500 finishing far from record highs hit during the session.
—By CNBC's Kate Gibson
Coming Up This Week:
Tuesday
Earnings: Alcoa, WD-40, International Speedway
7:30 a.m.: NFIB survey
10:00 a.m.: JOLTS
1:00 p.m.: $30 billion three-year auction
1:30 p.m.: Minneapolis Fed President Narayana Kocherlakota
2:45 p.m.: Philadelphia Fed President Charles Plosser
4:00 p.m.: Chicago Fed President Charles Evans on a panel at the IMF spring meeting
4:00 p.m.: Fed open meeting on rulemakings for leverage ratios
Wednesday
Earnings: Constellation Brands, Ruby Tuesday, Bed Bath and Beyond, Apogee
10:00 a.m.: Wholesale trade
1:00 p.m.: $21 billion 10-year auction
2:00 p.m.: FOMC minutes
3:30 p.m.: Chicago Fed's Evans on economy and monetary policy
7:30 p.m.: Fed Gov.Daniel Tarullo
Thursday
Earnings: Family Dollar, Pier 1 Imports, Shaw Communications, Commerce Bancshares, NQ Communications
Monthly chain store sales
8:30 a.m.: Jobless claims
8:30 a.m.: Import prices
8:45 a.m.: IMF Director Christine Lagarde press briefing
11:30 a.m.: Chicago Fed's Evans
1:00 p.m.: $13 billion 30-year auction
2:00 p.m.: Federal budget
Friday
Earnings: JP Morgan Chase, Wells Fargo, Fastenal
8:30 a.m.: PPI
9:55 a.m.: Consumer sentiment
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