Why did Timaru's grocery spending appear to drop by half in a single year? The answer isn't that Cantabrians suddenly stopped eating. It's that the data broke. and nobody seems to have noticed.

As RNZ reports households freezing their spending amid soaring bills, Stats NZ's food price index for Timaru tells a different story entirely: the region's figure plummeted from 15,445 in 2013 to just 7,836 in 2014. That's not a spending freeze. That's a statistical cliff. (Source: Stats NZ, food-price-index-detailed)

You have to go back to 1993 to find Timaru recording numbers this low. But 1993 was three decades ago, when New Zealand's population was 3.5 million and the average house cost $110,000. The idea that Timaru's food spending today matches levels from the early 90s doesn't pass the smell test.

What likely happened: a methodological change, a sample size adjustment, or a data collection gap that nobody flagged publicly. Regional food price indices depend on consistent sampling from retailers and households. When that sampling changes. stores close, survey participants drop out, weightings get revised. the numbers can lurch sideways without warning.

This matters because we're having a national conversation about the cost of living based on data that can lose half its value between one year and the next without explanation. When RNZ reports that households are putting spending "on ice," readers assume the underlying statistics are solid. But Timaru's trajectory from 2013 to 2014 suggests otherwise.

The trend before the drop was steady: 14,599 in 2010, inching up to 15,445 by 2013. Then the collapse. No recession that year explains it. No regional economic shock. Just a number that suddenly doesn't fit the pattern.

Here's the uncomfortable truth: if regional food price data can halve without triggering alarm bells, how much of the cost-of-living debate rests on similarly unstable foundations? When politicians cite food price indices to justify policy, are they quoting figures that reflect reality or statistical artefacts?

The broader point isn't about Timaru specifically. It's about what happens when the infrastructure for measuring hardship becomes as unreliable as the hardship itself. Households know their grocery bills are rising. they see it every week at the checkout. But the data meant to capture that pressure keeps vanishing, jumping, or flatly contradicting lived experience.

Somewhere between Timaru in 2013 and Timaru in 2014, 7,609 units of measurement simply evaporated. Nobody issued a correction. Nobody revised the series. The number just sits there in the dataset, an unexplained anomaly in the record of how much it costs to feed a family in New Zealand.