For many years, analysts and commentators have pointed to Koch Industries, the Kansas-based industrial conglomerate, and Cargill, the agricultural group, as the largest privately-owned US companies.

But in the FT Non-Public 150, McKinsey’s analysis of synthetic market capitalisation, the booming private equity industry is providing firms that are much larger. According to the study, Kohlberg Kravis Roberts, led by buy-out veterans Henry Kravis and George Roberts, is the largest privately-owned company in the US, and the largest privately-held financial services institution in the world, with a market value of $104bn.