The ages for peak happiness are 46 years apart. Or maybe not.

When are humans the happiest with their own lives?

The answer is not so simple — and it might depend on who you ask.

An extensive survey published in 2014 of more than 23,000 Germans conducted over 12 years found that life satisfaction peaked at 23. Then it slipped, reaching its zenith at 58 before rising again to another peak at 69.

“Some theories have assumed that the U-shape is caused by unmet expectations that are felt painfully in midlife but beneficially abandoned and experienced with less regret during old age,” according to the survey’s author, Hannes Schwandt.

A study of 2,000 Britons, however, found that 58 was actually when people are happiest, having found the right balance between work and life, according to the Daily Mail. The research, done by Samsung in 2014, found that people were most stressed at 35.

“It’s little wonder that our 30s are so stressful as we try — sometimes desperately — to juggle high-pressure jobs and family demands whilst maintaining happy relationships,” Cary Cooper, a professor at the University of Lancaster told the Daily Mail. “And then by the time we reach our 50s, we feel much more confident, allowing us to set the agenda when it comes to working hours and family life.”

But yet another survey, this one conducted by Friends Reunited in Britain, found that 33 was the magic number for happiness, according to a report by Time.

This survey from the “Midlife in the United States” found happiness is stable through your 20s and 30s before declining in your 40s and then rising again in your 60s.

And still another one by researchers at the University of Alberta and Brandeis University found slight differences among those with a high school degree — a sharp rise from 18 to 25, leveling off around 32 and a dip in the late 30s — and those with a college degree — a straight-line rise from 23 to 37, according to an article in Psychology Today.

This story was originally published April 14, 2017 at 7:21 PM with the headline "The ages for peak happiness are 46 years apart. Or maybe not.."