The annual income of US President Barack Obama and his wife Michelle dropped by more than two-thirds to $1.73 million in 2010 against $5.5 million in 2009, the White House has said.

Mr Obama and the First Lady filed their income-tax returns jointly and reported an adjusted gross income of $1,728,096, the White House Press Secretary, Mr Jay Carney, said in a blog posting on Monday, the last day of filing the tax returns for the year 2010.

“The vast majority of the family’s income is the proceeds from the sale of the President’s books. The Obamas paid $4,53,770 in total federal tax,” he said.

The family also reported donating $2,45,075 — or about 14.2 per cent of their adjusted gross income — to 36 different charities. The largest reported gift to charity was a $1,31,075-contribution to the Fisher House Foundation.

Mr Carney said that the President is donating the after-tax proceeds from his children’s book to a Fisher House scholarship fund for the children of fallen and disabled soldiers.

The President and the First Lady also released their Illinois income-tax return and reported paying $51,568 in state income taxes, the White House official said.

On the other hand, the Vice-President, Mr Joe Biden, and his wife, Ms Jill Biden, reported an adjusted gross income of $3,79,178. The Bidens paid $86,626 in total federal taxes for 2010. They contributed $5,350 to charity, in both monetary and in-kind donations, he added.