For the Gold Coast alone it was estimated to have a value of between $US1 to $US3.3 billion a year through improved mental health but also the lifestyle choices surfers make.

For the global economy the figure was closer to $US1 trillion.

The report said that mental health benefits from surfing comprised 57 to 74 per cent of the total economic benefits of surfing. The mental health benefits were 4.4–13.5 times direct expenditure by surfers, and 4 to 12 times economic effects via property and inbound tourism.

It found that if surfing reduced stress from high to low levels, it created an estimated 10 per cent improvement in per capita workplace productivity, plus 10 per cent reduction in costs of mental healthcare.

“The Australian mean per capita GDP is (about) $45,500, and mental healthcare costs are (about) 10 per cent of GDP.

“The value of that stress reduction via surfing is estimated at about $5000 per person per year.

“Surfing therefore contributes an estimated $0.65–2.10 billion per year via surfer mental health benefits.

“This can be injected directly into the Gold Coast economy via both employment and healthcare.

Griffith’s professor emeritus Ralf Buckley said the study’s aim was to estimate the large-scale economic value of mental health benefits across the entire representative population of individuals who took part in recreational surfing.

He had a similar approach in calculating the visitors to national parks.

“The economics are straightforward,” he said.  

“We simply took existing health economics calculations for parks and greenspace and applied them to surfing.”

However, the report said that as was the case with many “thrill-and-skill’’ adventure activities, surfing can act as a behavioural addiction.

“At least some surfers suffer substantial withdrawal symptoms if deprived of surf,’’ it said.

Outcomes were also sometimes be perceived as negative, with injuries and overcrowding as principal causes.

“The reason why there are such big numbers in the value of recreational activities like surfing for mental health benefits is that for almost every kind of job, you have to pay attention: for safety, skill, service, or decisions,” Professor Buckley said.

“If you are stressed and not paying proper attention, your job performance suffers, and that costs money for your employer or your business.

“Outdoor activities such as surfing reduce stress, as long as you can get a few good waves. Surfing has a powerful psychological effect and that has a substantial value.”

“The economic value of surf amenities also overlaps with beach amenities more broadly,” Professor Buckley said.