Lindsay Mitchell put me onto a quote by veteran grumbler Max Rashbrooke that the child poverty rate doubled in New Zealand:

In a system where income goes disproportionately to the already well-off, ordinary workers are missing out on the rewards of their efforts, to the tune of billions of dollars a year. Welfare benefits, cut by a quarter in 1991 and increased just 8 per cent in the last budget, are far too low to meet people’s basic needs.

The result is a doubling of child poverty and the return of childhood diseases unknown in most developed countries – a national embarrassment, as one researcher described it.

Poverty, income and inequality data is collected in loving detail by Brian Perry every year for the Ministry of Social Development.

Figure 1: % child poverty in New Zealand (before and after housing costs), 60% 1998 median constant value, 1982 – 2013

Source: Bryan Perry, Household incomes in New Zealand: Trends in indicators of inequality and hardship 1982 to 2013. Ministry of Social Development (July 2014), Tables F.6 and F.7.

The only thing noticeable in the downward trend in child poverty in New Zealand since its doubling with the sharp recession in 1990 with double-digit unemployment rates is child poverty stop falling shortly after in-work family tax credits were introduced in the form of Working for Families in 2005.

New QV figures show Auckland house prices are up a massive 16.1% on last year, now estimated to reach $1m by Aug '16. http://t.co/DwAU79ozCy—
New Zealand Labour (@nzlabour) June 09, 2015

There was a break in trend in the long decline in child poverty as soon as in-work family tax credits were introduced in New Zealand. I’m sure this is a coincidence because, as Brian Perry said when discussing the introduction of Working for Families in 2005:

The 2004 to 2007 period was the only one in the 25 years to 2007 in which the incomes of low- to middle-income households grew more quickly than those of households above the median.

The real killer in New Zealand in terms of poverty and inequality are housing costs. Housing costs are wholly under the control of government through its control of the supply of land, which is restricted at the behest of the parties of the left.

Figure 2: real equivalised household incomes (before and after housing costs): changes at the top of lowest income decile, New Zealand, 1982 to 2013

Source: Bryan Perry, Household incomes in New Zealand: Trends in indicators of inequality and hardship 1982 to 2013. Ministry of Social Development (July 2014), tables D.2 and D.4.

Figure 2 shows that real equivalised household income after housing costs has not grown and in fact has fallen for the bottom 10% of the income distribution in New Zealand.

It is the left-wing parties who oppose measures to reduce housing costs and and increase the supply of land through reforms to the Resource Management Act and the relaxation of the Auckland metropolitan urban limit.

Labour and the Greens are in effect keeping the poor poor to win middle-class votes.

Figure 3: real equivalised household incomes (before and after housing costs): changes at the top of the top, middle and lowest lowest income deciles, New Zealand, 1982 to 2013

Source: Bryan Perry, Household incomes in New Zealand: Trends in indicators of inequality and hardship 1982 to 2013. Ministry of Social Development (July 2014), tables D.2 in D.4.

Figure 3 shows that those in the middle and higher deciles, a political territory rich in swinging voters, are still doing well after housing costs. The parties of the left are collaborating with a middle-class home owning voter while betraying the working class and its aspirations from home ownership and quite simply affordable housing costs when they rent.

The increases for all groups may be understated by the inability of living standards measures to adequately account for new goods, product upgrades and rising life expectancies.