The number of men working into their 70s has leaped from one in 10 to one in four in the past 20 years.

The expected age of retirement for men has jumped 2.2 years to age 67 since 2014-15, KPMG Australia analysis of ABS Labour Force Survey data has also found.

For women, it has climbed by 1.1 years to 65.3 years.

The research also shows 10 per cent of men in their late 70s are still in the workforce. 

KPMG urban economist Terry Rawnsley believes that the lift in the age pension access age to 67 has caused many to stay in the workforce, and others have made the voluntary decision to delay retirement beyond the “official” age.

“People are looking for that mental stimulation. They want to have a reason to roll out of bed a couple of days a week, and also a little bit extra money coming in, [which is] helpful as well,” Rawnsley said.

He attributes the increase to the shift in work carried out by most people in the workforce, explaining that it is easier for a 70-year-old to work on a laptop rather than on a construction site.

“The adoption of working from home has made many older Australians realise they can ‘semi-retire’ and continue dabbling in the workplace part-time,” Rawnsley said.

Professor Andrew Brooks, 76, has worked as a urologist at Westmead Hospital for 40 years.

He currently works four and a half days a week, consulting and conducting minor surgeries.

“You can’t walk along the beach eight hours a day, seven days a week. You need something more exciting in your life,” he said.