Davos: The state of the world in seven snowballs

Income inequality and the gap between the richest and poorest is one of the items at the top of the agenda for the World Economic Forum taking place in Davos.

Swedish Professor Hans Rosling is a statistician who specialises in data visualisation and in tracking income disparities around the world.

As global and business leaders meet in the small Swiss ski resort he uses snowballs to explain how inequality in the world is changing.