It may have been a year of impeachment, trade wars and threatened military conflict in the Middle East, but Americans feel they have it better than ever before.

Nine out of ten US citizens are satisfied or very satisfied with their lives, according to a Gallup poll, a record since it was started more than 40 years ago.

American confidence in the economy also hit a 20-year high, it was found, following years of economic growth and rising employment.

It comes as President Trump launches his re-election bid to secure another four years in the White House after overseeing economic growth and record employment.

Nine out of ten US citizens are satisfied or very satisfied with their lives, a new record. (Pictured is incumbent President Donald Trump in the White House yesterday)

Those who voted Republican, are paid more than $100,000 or are married, were most likely to be satisfied or very satisfied.

The least satisfied citizens were those who are unmarried, Democrats or on less than $40,000, the poll revealed.

But even these groups showed high levels of satisfaction with 86 per cent of those without partners, 86 per cent of people and 80 per cent of those on lower wages voting Democrat saying they are 'satisfied' with their lives.

The pollster put the rise in confidence down to increased trust in the US economy and the improved health of personal finances.

'That two in three Americans are very satisfied is reflective of this upbeat moment in time,' they said, 'and whether these sentiments carry through the coming decade will be something to watch'.

The previous high was recorded in 2003, when 88 per cent of those asked said they were satisfied with their lives.

This came after the US defeated the Iraqi army and finished the war in May, and President Bush signed a $350 billion tax cut package, the third largest in US history.

The results were compiled after the pollster quizzed more than a thousand people between January 2 and 15 over the phone.

They contradict the World Happiness Report which said last year the US is the unhappiest it's ever been.

The country dropped to 19th on the table last year, it's lowest ever position, having ranked 18th in 2018 and 14th in 2017.

Countries including the United Kingdom, Finland and Costa Rica all ranked above the US.