American magazine Forbes has just released its annual rich list. There are now 1,226 US-dollar billionaires in the world, an all-time record. They are richer than ever before too – the group’s net worth is up 2% on last year, at $4.6trn, with the ‘average’ billionaire worth $3.7bn. But where do they live? The map shows the number of billionaires per country, with the top ten countries highlighted.