U.S. stocks fell, following the steepest decline for equities in more than a month, as weaker-than-estimated data added to concerns about slowing growth before Friday’s government jobs report.

Hewlett-Packard Co. and Microsoft Corp. dropped for a third session, weighing on technology shares. Alexion Pharmaceuticals Inc. tumbled 10 percent after agreeing to buy Synageva BioPharma Corp. for $8.4 billion, and Pfizer Inc. declined as health-care slumped. Devon Energy Corp. rose more than 2.2 percent after boosting its production forecast.

The Standard & Poor’s 500 Index fell 0.7 percent to 2,075.15 at 2:01 p.m. in New York, after earlier rising as much as 0.4 percent. The Dow Jones Industrial Average declined 133.53 points, or 0.7 percent, to 17,794.67 and has erased its 2015 gain. The Nasdaq Composite Index lost 0.7 percent, while the Russell 2000 Index was little changed as biotechnology shares rose.

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“The data this morning has people nervous, and after yesterday’s selloff, there are a lot of weak hands in the market,”said Robert Pavlik, who helps oversee $9 billion as chief investment strategist at Boston Private Wealth. “People are worried about what Friday’s report is going to bring. They’re not fully committed — they’re just trying to ride the wave, and that’s caused some selling pressure to develop.”

Equities briefly extended their declines earlier after Federal Reserve Chair Janet Yellen said equity market valuations are quite high and could be a potential source of financial instability, in remarks on a panel in Washington.

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Growth Concerns

Investors have been listening intently to commentary from Fed policy makers and watching economic data for clues on the timing of future interest-rate increases.

Companies added 169,000 workers to payrolls in April, according to the ADP Research Institute, below the 200,000 median forecast of economists surveyed by Bloomberg. Friday’s monthly government payrolls numbers are expected to rise 230,000, according to economists’ estimates, after a 126,000 gain in March.

A separate report today said productivity fell in the first quarter while labor costs increased, a dynamic that could weigh on corporate profits. Economic data this month have been missing estimates by the most in more than six years, stoking concerns the Fed may soon raise borrowing costs even as the economy slows.

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The S&P 500 has fallen 2 percent from a record last month as mixed data added to worries on U.S. growth while concern rose that Greece won’t be able to resolve its debt crisis.

Tech Retreat

MetLife Inc., 21st Century Fox Inc. and Prudential Financial Inc. are among companies releasing earnings today. S&P 500 companies are beating earnings estimates and analysts are getting more optimistic. They project index members’ profit fell 0.4 percent in the first quarter, compared with 5.6 percent at the start of the earnings season. They still forecast quarterly declines through September.

The Chicago Board Options Exchange Volatility Index climbed 9.6 percent Wednesday to 15.68. The gauge, know as the VIX, jumped 11 percent Tuesday and is headed toward its biggest two-day gain since January.

All of the S&P 500’s 10 main groups fell for a second day, with utility, phone and technology companies the biggest decliners. Microsoft and Hewlett-Packard Co. slid at least 2.1 percent, on track for their biggest drop in six weeks. Intel Corp. lost 2.1 percent after dropping 2.4 percent yesterday.

Frontier Communications Corp. tumbled 11 percent after first-quarter profit and revenue missed estimates to lead a slide among phone companies.

Biotechs Gain

Alexion Pharmaceuticals’ 10 percent retreat along with Pfizer’s 1.6 percent decline weighed the most on the health-care group. Meanwhile, the Nasdaq Biotechnology Index rose 0.4 percent, after falling 2 percent yesterday, as biotechs gained amid Alexion’s buyout of Synageva. Synageva surged 113 percent.

News Corp. lost 6.6 percent, pacing declines among consumer discretionary shares after reporting quarterly earnings that missed analysts’ estimates after print advertising continued to fall and currency swings ate into revenue. Shares fell the most since July.

Western Union Co. gained 3.4 percent, paring an earlier advance that took shares to a more than six-year high, after denying a report that it’s in talks to acquire smaller rival MoneyGram International Inc. MoneyGram rallied 19 percent.

Electronic Arts Inc. rose 3 percent to its highest level in more than seven years as fourth-quartersales and earnings beat analysts’ forecasts.

Cablevision Systems Corp. jumped 4.7 percent to a five-month high after Chief Executive Jim Dolansaid at a panel at the Internet & Television Expo that he wants a deal with Time Warner Cable Inc. Time Warner slipped 0.9 percent.