While belief in God remains strong in the US, the Gallup poll also found that nonbelief has risen from one per cent in 1944 to seven percent today.

The percentage of Americans who affirm their belief in God has decreased slightly from 96 percent in 1944 to 92 per cent today.

The survey, released Friday, was conducted between May 5 and 8 among more than 1,000 adults.

Notably, those least likely to believe in God are 18 to 29-year-olds. Only 84 per cent agreed that they believe in God compared to 94 per cent of older Americans.

Liberals, Americans from the East, and those with postgraduate education were also found to be less likely to believe in God, though a majority (more than eight in 10) still do.

While the Gallup report noted that belief in God has been relatively constant over the last six decades, it also highlighted that when Americans are given other options (such as universal spirit or higher power) or the ability to express doubts, then the percentage of those certain in their beliefs drops.

A 2010 Gallup poll revealed that 80 per cent said they believe in God while 12 per cent opted belief in a universal spirit or higher power.

When provided with more options about their belief, fewer Americans were found to be absolutely certain about God's existence.

A 2006 Gallup poll showed that 73 per cent were convinced that God exists while 14 per cent said God "probably exists" and had little doubt. Another five per cent chose the option that God probably exists but they have a lot of doubt. And three per cent said they were convinced God does not exist.

Compared to the rest of the globe, the US is still found to have strong belief in God. An Ipsos Social Research Institute survey earlier this year found that just over half (51 per cent) of people worldwide express belief in God.