Weak wage growth throughout the western world has been caused by the rise of part time work in recent decades, according to the International Monetary Fund.

Flexible working allowing companies to raise or cut the number of hours on offer rather than having to offer more money to tempt new workers to join their firms.

This, combined with weak productivity growth, has resulted in sluggish wage rises.

Unemployment has fallen sharply since the financial crisis with joblessness in the UK at its lowest level in 42 years. Usually that would be expected to push up wages.

But the IMF fears that this headline figure - across the world - hides the nature of those jobs, with temporary, flexible and part time work putting downward pressure on pay growth.