A new study from the US has major implications for the impact that ethnic and gender diversity in private equity firms can have on returns. 

According to the National Association of Investment Companies, its members' returns have clocked in at an average median net IRR of 15.2 per cent versus a US industry average of 3.7 per cent. Taken alone, US buyout funds have produced an average return of 7.1 per cent. 

Whether causality or coincidence, NAIC member firms can boast industry-beating diversity. Ethnic minorities own 50 per cent or more of 11 of the association’s 14 firms. 

Not only that but more than two-thirds of NAIC firms' investment teams are made up of at least 50 per cent women or minorities. 

The association’s members include mid-market US firms such as Bank of America Merrill Lynch Capital Access Partners, Palladium Equity Partners and Vista Equity Partners rather than blue-chip mega firms. 

Buyout houses in the top end of the market jostled for assets during the boom years, pushing up prices as banks and bond investors were willing to lay on leverage for deals. 

The mid-market, meanwhile, benefitted from the relative quiet before the crash and LPs began re-evaluating their strategies. 

GPs can also have more direct influence over smaller businesses and there is more growth to be had when compared to large corporations backed by private equity. 

While the NAIC's findings are far from conclusive, Bloomberg data shows that at nine of the ten biggest firms in the US, women account for 8.1 per cent of the most senior and best paid roles.