President and First Lady earned $5.5 million last year

US President Barack Obama and his wife Michelle earned $5.5 million in 2009, mainly from book sales, according to the White House.
The couple have doubled their income since Mr Obama took office in January 2009, tax returns show.

The figure excludes Mr Obama's $1.4 million Nobel Peace Prize, which he donated to 10 charities.

A third of the couple's income, totalling more than $1.8 million, was paid in tax.

The details were revealed by the White House on 15 April, the US deadline to file tax returns.

Most of the earnings came from royalties of sales of the president's books, Dreams of My Father and The Audacity of Hope, which have become bestsellers.

In addition to the Nobel Prize money, the Obamas donated $329,100 to 40 different charities, about 6% of their income.

Their earnings far exceed those of Vice-President Joe Biden and his wife, Jill, who reported a joint income of only $333,182 for 2009.

In 2008, the Obamas earned $2.65 million.