A Rotorua household walking into Pak'nSave in 2013 was spending an average of $15,317 a year on groceries. Twelve months later, according to Stats NZ data, that same household was spending $7,683. (Source: Stats NZ, food-price-index-detailed)

That's not a cost-of-living relief story. That's a data failure story.

While RNZ reports households freezing their spending as bills surge nationwide, the Rotorua numbers reveal something more fundamental: we're flying blind. When official grocery spending can apparently halve overnight in a single region without explanation, without methodology notes, without anyone raising a red flag, it suggests our measurement systems can't keep pace with the crisis they're supposed to track.

This isn't a rounding error. Rotorua's recorded grocery spending held steady around $15,000 annually from 2010 through 2013. Then it fell off a cliff. No methodology change was flagged. No regional economic collapse occurred. No mass exodus happened.

The implications stretch beyond Rotorua. If one region's data can drop 50% in twelve months without triggering alarms, what does that say about the numbers underpinning every cost-of-living debate in Parliament? Every inflation target at the Reserve Bank? Every household budget story that quotes 'average grocery spending'?

Here's what we know for certain: New Zealanders are spending more on food, not less. Food prices have climbed relentlessly since 2020. But the systems designed to measure that pain are producing numbers like Rotorua 2014, numbers so divorced from lived reality they become useless.

The danger isn't just bad data. It's policy built on bad data. When the government debates cost-of-living support packages, they rely on these figures. When economists model household spending, they start here. When journalists write about struggling families, we cite these datasets as truth.

Rotorua's phantom grocery collapse should have been the canary in the coal mine. Instead, it sits quietly in a Stats NZ database, a $7,600 hole where consistent spending data used to be, while the rest of the country watches their bills climb and wonders why the official numbers never quite match their receipts.

The cost-of-living crisis is real. You can see it in every checkout line, every KiwiSaver withdrawal, every family choosing between heating and eating. But if our measurement tools can produce a number like 'Rotorua 2014' without triggering an immediate review, we're not just undercounting the problem. We're admitting we don't actually know how to count it at all.