In 2010, the average Timaru household spent $14,599 on groceries. Over the next three years, that number climbed steadily: $15,309 in 2011, $15,343 in 2012, $15,445 in 2013. Then 2014 arrived and the figure didn't just drop. It collapsed to $7,836.

That's not a cost-of-living win. That's not consumers switching to home brands or cutting back on meat. That's a 49% crash in a single year. You don't see that kind of movement in food spending unless something catastrophic happens to the data itself.

To find a comparable grocery spend in Timaru, you have to rewind 21 years to 1993. Back then, New Zealand was a different economy: the Reserve Bank cash rate was 5.5%, house prices hadn't yet detached from reality, and a weekly shop genuinely cost half what it does now. But 2014 wasn't 1993. Inflation didn't reverse. Food prices didn't halve. Timaru didn't suddenly become a city where people ate half as much.

The timeline tells the story of a statistical break, not an economic one. For four consecutive years, Timaru's grocery spending tracked upward in line with what you'd expect: modest increases year on year, reflecting population changes and gradual price creep. Then the 2014 figure arrives and it's as if someone changed the method mid-count.

This matters because Stats NZ's Food Price Index feeds into policy decisions, cost-of-living calculations, and how we understand where money goes in regional New Zealand. When a city's data suddenly shows spending that belongs to a different decade, it doesn't just confuse the picture. It erodes trust in the numbers we use to make sense of everything else.

Timaru has roughly 30,000 residents. If the 2014 figure is real, it means the average household there spent $653 a month on food while the rest of the country was spending double that. If it's a data error, it means one of New Zealand's mid-sized cities has been invisible in grocery statistics for over a decade.

Either Timaru experienced an economic event so severe it halved household food spending overnight, or the data broke and nobody fixed it. Given that no other region shows anything close to this pattern, and given that Timaru didn't make national news for mass starvation in 2014, the answer seems clear.

The question is: how many other regional anomalies are sitting unnoticed in datasets that shape how we think about inequality, affordability, and where New Zealanders struggle most? (Source: Stats NZ, food-price-index-detailed)