SINGAPORE - Two wars, a crashing economy bleeding millions of jobs, and hardly a hair out of place.

Former United States president Barack Obama on Monday (Dec 16) shared his hack for maintaining his famed cool in stressful situations before an enthralled audience of more than 4,500, mostly professionals and company executives from Singapore and around the region.

The "no-drama Obama" has not faded from public view after handing over the baton to Mr Donald Trump in 2017 upon completing eight years in office.

During the discussion organised by Australian business events provider The Growth Faculty at the Singapore Expo, he dwelt on the topic of leadership in an hour-long conversation with Mr Nicholas Fang, director of Security and Global Affairs at the Singapore Institute of International Affairs.

Recalling the tumultuous period as he stepped into office in 2008, in the shadow of the sub-prime crisis that devastated the US economy and rocked nearly all other economies linked to it through trade and finance, Mr Obama said that his plate was full.

"The economy was contracting more rapidly than it did during the Great Depression.

"We were shedding 800,000 jobs a month, month after month, in six months prior to when I came into office. In total, we lost 8 million jobs."

The question often posed to him was why he did not get more stressed.

"I attribute some of this to my Hawaiian/Indonesian vibe," he said, harking on his childhood in Indonesia from 1967 to 1971, when he moved back to his birthplace of Honolulu.

"I didn't get too high, buy all the hype when you are on the posters, on the cover of magazines... I didn't get too low when things were tough partly because I was confident that we were making the best decisions possible in the circumstances."

The secret, he said, was a two-ingredient sauce: people and process.

"If you are in any kind of leadership situation, your first job is to put together the best possible talent, people who have integrity, who subscribe to your work values and believe in your vision.

"You put them in positions to succeed and you make decisions based on best available information and setting up a process where you are able to see from every angle what kind of solutions you might come up, to the problems you are facing.

"All the problems I was facing were hard. If you are in the White House, in the West Wing, the only issues that came to my desk were ones that had no good solution and nobody else could solve.

"If somebody else could solve it, they would have solved if before they got to me.

"We had the expression - and I believe you would have an equivalent here - that poop does not roll downhill in the White House, it rolls uphill... to me," he said, as laughter broke out in the hall.

"It landed up on my desk... Clean it up!"

He said he always found himself grappling with probabilities.

"You did not know for certain that any particular solution would work. Should we intervene in the auto industry? Should we save all three automakers or just one? Can we stop the bleeding... through this particular policy versus that one?

"They were always 55-45, 70-30 solutions, there was always the probability of failure.

"But what we were able to do was to set up a process that I trusted, where I had confidence that we looked at every problem from every angle, using logic and reasoning, and facts and data.

"So I could go to sleep at night feeling as if what I decided may not work, but nobody could have made a better decision than I made in that circumstance. That we had set up a great process and I had great people.

"And that's how I was able to manage stress throughout the presidency and I could feel like we did the best we could and for the right reasons. And we maintained our integrity throughout and didn't have major scandals.

"We made mistakes but we maintained high ethical standards," he said.

Although Mr Trump was never mentioned by name, there were allusions to his policies in Mr Obama's responses which were critical of the stark political polarisation evident in the US today.

Mr Obama leaves Singapore later on Monday after arriving here last Friday to participate in a charity event. He also met Prime Minister Lee Hsien Loong the same day.

He was accompanied by his wife Michelle, who discussed themes from her bestselling memoir Becoming on Saturday at a talk at the Singapore Expo.

Mr Obama is working on his new memoir which is expected to be released next year as the US holds a presidential election.

The Obamas inked a deal with Netflix last year to produce a set of films and series under their new production company, Higher Ground Productions.

According to a New York Times report in 2017, Mr Obama's speaking fees per engagement are as much as US$400,000 (S$543,000), equal to his salary as president and twice the rate commanded by former President Bill Clinton.