The first relates to demography.

finds that a one-percentage-point rise in the immigration rate boosts average house prices by 3.3%.

The second factor relates to cities.

We calculate that the share of the rich world’s overall employment taking place in capital cities has grown in recent years

All this raises competition for living space in compact urban centres, where the supply of housing is already constrained.

The city’s triumph compounds the effects of the third factor: infrastructure.

Many governments find it nearly impossible to build new transport networks to lighten the load.

The supply problem remains most acute in cities, where regulations are strictest.