U.S. stocks slipped in light trading, with the Standard & Poor’s 500 Index posting back-to-back declines for the first time this month, as investors considered the capacity of central banks to boost global growth.

The complexion of Tuesday’s retreat mirrored yesterday’s results, with commodity companies among the biggest losers, joined again by health-care and financial shares. Valeant Pharmaceuticals International Inc. plunged 51 percent after cutting its profit forecast. Apple Inc. added 2 percent amid positive analyst comments on iPhone sales, while baby formula maker Mead Johnson Nutrition Co. surged 11 percent on deal speculation.

The S&P 500 declined 0.2 percent to 2,015.91 at 4 p.m. in New York, trimming an earlier 0.7 percent slide.

U.S. equities retreated with shares in Asia and Europe after the Bank of Japan refrained from adding more stimulus. Central banks around the world have indicated a willingness to continue measures to support economic growth and stabilize markets, helping stocks rebound in the past month. The Federal Reserve kicked off a two-day policy meeting today, with investors tempering their trading before the outcome Wednesday afternoon.

Traders are pricing in little chance of a rate increase, though bets for a boost later in the year have risen. The probability of a June move is now seen at almost 54 percent, from 2 percent a month ago.

Source : Bloomberg