Two in five people working in British banking have parents who also worked in the sector – more than three times the national average for other types of jobs.

Some 41% of financial services employees had parents working in the same sector, against a national average of 12% across other sectors, research by the accountants KPMG showed. In insurance, more than half of staff had followed their parents into the industry.

Tim Howarth, head of financial services consulting at KPMG, said: “The fact that people in financial services are more than three times more likely than the national average to have followed in their parent’s career footsteps is staggering.”

Howarth said the lack of diversity in banking had resulted in “a narrow and narrowing talent pool and not enough social mobility.”

Diversity in banking is unlikely to improve, as young people working in financial services are even more likely to have followed their parents into the sector. Some 55% of bankers aged between 16 and 24 had parents who also worked in the industry, according to the poll of 500 UK financial employees, which was compared to the results for 1,000 Britons working in other sectors.

The survey found that pay was the biggest motivation for those seeking jobs in financial services. Some 31% said it was their main reason to work in the sector, compared with 16% who said interesting work was the main driver, and the same proportion who said they wanted the opportunity to progress in their careers.

Outside financial services, only 16% of workers said pay was their main motivation for their choice of job.

The financial services sector employs about 2.3 million people in the UK, accounting for one in every 14 jobs, according to TheCityUK, a lobby group. While financial services is the biggest contributor to tax revenues of any sector, the banking industry has been a focus for campaigns against inequality since the financial crisis just over a decade ago.

John Mann, a Labour MP who sits on the financial services select committee, said the lack of diversity in banking was a “huge challenge”.

“Its biggest problem, by far, has been its cultural problem,” he told Reuters. “That’s what’s led to the collapse of a number of financial institutions. The cultural problems are reinforced by not bringing in a wider array of people.”

Two-thirds of all the people surveyed said they would not consider a role in financial services. Of these, 41% said it was because the industry “sounds boring”, while 16% cited a lack of contacts in the sector. Howarth said: “There’s clearly a gap between what the public think, and the realities of working in financial services... that has to be addressed if we are to attract the diverse mix of skills and experiences needed to navigate the changes going on in financial services and society.”