U.S. President Barack Obama's job approval rating during his first year in office averages 57 percent, among the lowest when compared with his predecessors, according to an opinion poll released by Gallup on Monday.

When Obama took office, his initial approval ratings were among the highest for a new U.S. president, with the first-quarter approval averaging 63 percent, said Gallup.

However, his public support dropped, with a sharp, nine-percentage-point decline from his second to third quarter in office, and the final-quarter average stands at 51 percent.

Compared with the first-year averages of other U.S. presidents elected to office since World War II, Obama's average ranks on the low end, tied with Ronald Reagan's, but better than Bill Clinton's historical low of 49 percent, said Gallup.

One of the factors leading to Obama's recent slump is Americans ' dissatisfaction with his handling of the economy. Although U.S. economy seems to be recovering from its worst recession in history, Obama's approval rating for handling the economy has declined over the course of the year and reached a new low of 40 percent in the most recent USA Today/Gallup poll.

The president's approval is further dragged down by his healthcare overhaul, top on his domestic legislative agenda, with only 37 percent in favor of his endeavors on this issue.

Gallup polled more than 40,000 American adults, aged 18 and older, through telephone interviews, between October 2009 and January 2010.