The 2013 Census data is a treasure trove. A striking regional picture is the unemployment rate by territorial authority.
I assumed a NAIRU of 5% for illustration; blue is less than NAIRU and red is higher. It shows the impact of a number of secular forces (ageing, urbanisation, contrasting industry performance, etc). The unemployment rate is generally lower in the South Island than in the North Island – with labour in relative scarcity and better utilised in the South Island compared to the North Island.
Given this information is not possible to glean from the Household Labour Force Survey (HLFS), it reinforces the need to do the Census at regular intervals (in addition to some surprises on population size, location, age, etc).