Carlos Slim tops Forbes rich list for fourth year
4 March 2013 Last updated at 16:21 GMT
Mexican tycoon Carlos Slim has topped Forbes magazine's list of the world's richest billionaires for a fourth year.
The magazine estimates that Mr Slim, whose business interests range from telecommunications to construction, is worth $73bn (£49bn).
He is followed by Microsoft founder Bill Gates on $67bn.
Clare O'Connor is Forbes' wealth writer.