Fintech firms with female founders are better investments.

That’s the conclusion from KPMG, which surveyed 91 financial-technology companies in the U.K., including nine where at least one founder was a woman.

The report, published Friday, showed that firms with a female founder have more than double the internal rate of return on average than peers where the initial entrepreneurs were all male.

KPMG acknowledged some limitations to the study, saying one large female-founded firm, London-based Starling Bank Ltd., which has raised 233 million pounds ($303 million), might skew the results. Still, it said the findings are important.

“While the number of female founders or co-founders is low, the fact that they typically achieve a higher rate of return is a clear vote for more diversity,” Anton Ruddenklau, global co-leader for fintech at KPMG, said in a statement.

Given many startups are unprofitable, KPMG largely based its analysis on valuation increases from one funding round to another.