'There are only two families in the world, as a grandmother of mine used to say: the haves and the have-nots.' Sancho Panza's line in Cervantes' famous novel was echoed by socialist Prime Minister Pedro Sánchez on Monday when he worried that Spanish society was rapidly dividing into two classes: 'Those who inherit properties from their parents and those who have to spend their lives working to pay the rent.'

Spain certainly has a severe housing crisis. Although the fertility rate of 1.3 children per woman is far below the 2.1 needed to maintain population, mass immigration means that every year the country needs to find homes for over half a million more people. But not even half of the estimated 250,000 new dwellings that are needed are being built. Over the last decade, average house prices have soared by 56 per cent - far outstripping the increase in wages. It's no surprise then that public anger is also rising rapidly.