Just how big and stubborn a productivity problem New Zealand has is starkly laid out in a new paper from the Productivity Commission.

Economic problems do not get more fundamental than this, if only for the obvious reason that income has to be earned before it can be spent, or taxed. And we are really not very good at doing that.

The commission starts by comparing New Zealand's gross domestic product per capita with the average of countries in the top half of the OECD ranked by income. It is a group which includes all the countries we like