While RNZ reports households freezing their spending amid soaring bills, there's a number in the official food price data that tells a different story entirely. one about the data itself.

In 2010, the Stats NZ food price index recorded 14,652 for Wanganui. Over the next three years, it climbed steadily: 15,404 in 2011, 15,641 in 2012, then held at 15,641 in 2013. (Source: Stats NZ, food-price-index-detailed)

Then something broke.

In 2014, the figure dropped to 7,798. Not a small adjustment. Not a regional quirk. A 50% fall in a single year.

This isn't a story about Wanganuians suddenly eating half as much. It's a story about what happens when the scaffolding holding up our cost-of-living debate shifts beneath us without warning.

Stats NZ's food price index doesn't measure individual grocery bills. It tracks price movements across categories. fruit and vegetables, meat and seafood, restaurant meals. Regional breakdowns like Wanganui's are modelled estimates, not direct surveys of every checkout counter in town.

So when a figure halves overnight, it's almost certainly a methodological change. Maybe the sample size shifted. Maybe the weighting formula was revised. Maybe Wanganui got folded into a different regional grouping, and nobody updated the footnotes.

The 2014 figure of 7,798 is the lowest in the dataset since 1993. not because food got cheaper, but because something in the counting changed.

Here's why this matters right now: we're in the middle of a national argument about the cost of living. Every political party has a theory. Every household has a breaking point. And all of it rests on data like this.

When a regional food price figure can lose half its value in a year without explanation, it raises an uncomfortable question: how much of what we think we know about cost-of-living trends is built on numbers that shifted for reasons nobody bothered to document?

Wanganui's grocery bills didn't halve in 2014. But the data did. And if you're using this dataset to argue about whether families are better or worse off than five years ago, you're standing on quicksand.

The figures from 2010 to 2013 tell a coherent story: steady climb, modest increases, the kind of trajectory you'd expect during recovery from the global financial crisis. Then the 2014 drop erases all of it, rendering any long-term comparison meaningless.

This is the hidden cost of the cost-of-living crisis: not just what we're paying, but what we're basing our decisions on. When the data itself can't hold still long enough to track a trend, every conclusion drawn from it becomes provisional at best.

Soaring bills are real. Household budgets are stretched. But the numbers we're using to measure the damage? Sometimes they're telling us more about Stats NZ's internal processes than about what's actually happening in kitchens across the country.