He will add to his coffers through his memoirs - publishers have described his presidential memoirs as the most hotly-anticipated ever, with advances estimated between $25 and $45 million.

On the speaking circuit, he can command unrivalled sums - George W. Bush earns between $100,000 and $175,000 per appearance, while Mr Clinton can earn $225,000. Mr Obama will outshine them both.

He is unlikely, however, to spend his time focused on how to boost his bank balance.

Mr Obama began his political career as a community activist on the South Side of Chicago; his life after the White House is expected to see a return to his roots.

“I’ll be 55 when I leave,”he told The New Yorker, knocking on a wooden end table. “Assuming that I get a couple more decades of good health, at least, then I think both Michelle and I are interested in creating platforms that train, empower, network, boost the next generation of leadership.

“And I think that, whatever shape my presidential center takes, I’m less interested in a building and campaign posters and Michelle’s dresses, although I think it’s fair to say that Michelle’s dresses will be the biggest draw by a huge margin.

“But what we’ll be most interested in is programming that helps the next Michelle Obama or the next Barack Obama, who right now is sitting out there and has no idea how to make their ideals live, isn’t quite sure what to do - to give them resources and ways to think about social change.”