Want long-lasting satisfaction? Find someone your own age

If you're looking for long-lasting satisfaction it may pay to find a partner close to your own age.

That's one possible reading of a recently published study into the marital satisfaction of differently aged couples.

The report, published in the Journal of Population Economics, was co-authored by Deakin University's Wang-Sheng Lee and Terra McKinnish from the University of Colorado.

Many people believed they would be happier with a younger spouse, Dr Lee told ABC Radio Melbourne's Richelle Hunt and Brian Nankervis.

"Everybody has heard of the half-your-age-plus-seven rule, where people think it's acceptable to have a younger spouse," he said.

"What is more interesting from our perspective is how this marital satisfaction evolves over time for couples where there is an age gap."

Short-lived satisfaction

The study was conducted using data from the Melbourne Institute's HILDA survey, which follows the lives of more than 17,000 Australians.

It found that newlyweds, be they men or women, were less satisfied with an older partner.

Both men and women were more satisfied than average when their partner was younger, but this increased satisfaction was short-lived.

"The higher levels of satisfaction were erased after about six to 10 years, because it seemed they were more financially vulnerable," Dr Lee said.

He said the data suggested that couples with a large age gap were more likely to be living on a single income.

"This also could contribute to them being more financially vulnerable if something bad happens."

Not about Donald Trump or George Clooney

Dr Lee said one possible explanation for the findings was that couples who were closer in age had more shared experiences.

"We believe that couples who are of a similar age are more likely to talk about plans for the future, because they are at similar phases of their careers and their lives."

He said the study looked at averages over the population surveyed, and each individual relationship was unique.

"It's not making a statement about the French president, Donald Trump, George Clooney or any of the other Hollywood celebrities — we're just saying something more about the typical Australian couple."