The number of Americans applying for first-time unemployment benefits rose dramatically last week to 360,000, an increase of 37,000, which was far more than the number analysts were expecting.

Analysts polled by Thomson Reuters I/B/E/S expected, on average, claims for the seven days ended Saturday to rise to 330,000 from the previous week's 323,000.

For the seven days ended May 4, claims fell to 323,000, a decrease of 4,000 from the previous week's revised figure of 327,000. The four-week moving average was 336,750, a decrease of 6,250 from the previous week's revised average of 343,000.