Highest gross income in a single year by a private citizen

The highest gross income ever achieved in a single year by a private citizen is an estimated $105 million (then £21.5 million) in 1927 by the Chicago gangster Alphonse ("Scarface Al") Capone (1899–1947). This was derived from illegal liquor trading and alky-cookers (illicit stills), gambling establishments, dog tracks, dance halls, "protection" rackets and vice. On his business card Capone described himself as a "second hand furniture dealer". This figure would be the equivalent of approximately $1.41 billion (£0.83 billion) in 2014.