The child poverty statistics due to be released next Tuesday are liable to make challenging reading.
And not just for the Minister for Child Poverty Reduction, Jacinda Ardern.
But also for those old enough to remember when the assertion that New Zealand is a great place to bring up kids did not invite this response: "Oh yeah? Depends whose kids."
This week Statistics New Zealand released numbers on household incomes and housing costs. Though nominally for the year to June 2020, the data was collected over the nine months to March 2020; thereafter the lockdown ruled out the face-to-face interviews the household economic survey relies on.
They give a picture of entrenched income inequality, with more of the population falling below all but one of the seven statutory measures of a poverty line.
Though this reflects the situation pre-Covid, it is unlikely to have improved since then.
On top of that there is the regressive impact of inflation, which is harder on the poor.
The broadest measures of income inequality are essentially unchanged.
When households are ranked by income (after tax and adjusted for differences in household composition) one that is 20 per cent down from the top had an income 2.6 times larger than one 20 per cent up from the bottom. That ratio is unchanged from 2019.
Similarly, if you compare incomes at the 90th and 10th percentiles, the former is 4.1 times the latter, as it was in 2019.
For data nerds, the Gini coefficient — a measure of inequality — improved slightly from 32.7 to 32, but the improvement is within the margin of error.
These numbers cover all households and not just those with dependent children, but the latter are unlikely to be better off than households generally, especially if they rent.
The Child Poverty Reduction Act, enacted in 2018 to impose transparency on all this, specifies nine measures of household poverty by which progress is to be measured.
Seven are based on relative incomes. All but one have got worse. Depending on where the poverty line is drawn, between 12.5 and 24.1 per cent of the population fall below it.
Two metrics which improved reflect material hardship, measures that relate to how many of 17 indicators of deprivation a household satisfies. Things like whether they could afford a meal with meat, fish or chicken (or a vegetarian equivalent) at least every second day. Or two pairs of shoes? Or suitable clothes for a special occasion? Or home contents insurance? Or to give birthday or Christmas presents?
Respondents are also asked if in the past 12 months they found they could not pay electricity, gas, rates or water bills on time. Or put off visiting the doctor or dentist? Or had to put up with being cold? Or borrowed from friends or family to meet everyday living costs? Or, if they had an unexpected and unavoidable expense of $500, could they pay it within a month without borrowing?
Clearly, any progress on those things is welcome.
But the effects of the housing crisis on consumer spending power jump out from the latest data.
The share of disposable income pre-empted by housing costs is inversely related to household incomes.
For 33 per cent of the poorest fifth of households ranked by income (which are those with an after-tax income of $36,000 or less) housing costs gobble up 40 per cent or more of their income.
By contrast, for those in the highest income quintile (with disposable household incomes $123,000 or more) only 3 per cent have committed more than 40 per cent of their income to housing.
Some 51 per cent of households are owner-occupiers, two-thirds of whom are paying off a mortgage. Another 13 per cent are living in dwellings held in trust for their occupants, half of whom are paying a mortgage.
Some 34 per cent of households rent.
Guess who has fared better?
The 2019/20 household economic survey found mortgage interest payments had fallen 6.7 per cent or $17.30 a week on average compared with the year before, while rents were up 4.1 per cent.
And that was before the further round of mortgage rate cuts triggered by the Reserve Bank easing monetary policy in response to Covid.
The consumers price index does not include interest costs, but Statistics NZ publishes a series, "all groups plus interest", which does. The CPI rose 1.4 per cent in calendar 2020, but when interest costs are added it rose only 0.3 per cent.
In other words falling interest rates offset most of the increase in the cost of living for households with mortgages. Rents, by contrast, rose 2.9 per cent.
For the Reserve Bank this is a feature, not a bug. One of the main ways cutting interest rates lifts demand and activity in the economy is by giving people with mortgages more to spend on other things.
Another is the wealth effect from the associated house price inflation, when homeowners spend a few cents in the dollar of the increase in their equity.
The effects of housing costs are also apparent in the household living-costs price indices (HLPIs). These reweight the 700 or so items in the CPI basket to more accurately reflect spending patterns for subsets of households and usefully include interest costs.
In calendar 2020 the lowest spending fifth of households on average saw their cost of living rise 1.4 per cent. The highest spending fifth saw a zero increase.
Underlying this stark disparity is the fact that the lowest spending quintile spend on average 18.1 per cent of their income on rent and just 2.5 per cent on interest. For the highest-spending quintile it is 4.9 per cent rent but 9.1 per cent interest.
The regressive effects of inflation are nothing new. Over the past 10 years the HLPI for the lowest spending fifth of households has risen an average 1.75 per cent a year, compared with 1 per cent for the highest-spending fifth.