In 2022, the South Island's food price index sat at 13,735. Twelve months later, it had rocketed to 15,064. That's a jump of $1,329 in a single year.

Then, between 2023 and 2024, it crept up by just $72.

The slowdown is real. But here's what the numbers don't tell you: that $1,329 surge isn't money that came back. It's still in your weekly shop. The sticker shock from 2023 became the new baseline.

Wind back to 2020, when the index stood at 12,509. In four years, it climbed 2,796 points. That's a 22% increase in what South Islanders pay for the same trolley of food. A family spending $250 a week on groceries in 2020 now spends $305 for the same items.

The 2022-to-2023 spike was the sharpest in the dataset's modern history. It came as global supply chains buckled, fuel costs surged, and drought hit key growing regions. Families felt it in real time: bread, milk, vegetables all jumped within months.

The 2024 slowdown reflects inflation easing, not prices falling. The index measures change, not absolute cost. When it rises by $72 instead of $1,329, that's progress by comparison. But the cumulative weight of those prior years remains.

Consider what this means for a Christchurch household. If they spent $300 a week on groceries in 2020, they're now spending around $366 for the same basket. That's an extra $3,432 a year. For a family on a fixed income, or renters already stretched by rising housing costs, that's not a statistic. It's the difference between saving and breaking even.

The trajectory tells a story about momentum. The 2020-to-2021 increase was modest: 257 points. Then 2021 to 2022: 969 points. Then the 2022-to-2023 explosion. Now, finally, a plateau.

But plateaus don't erase peaks. Every dollar added in those surge years is still there, baked into the price of butter, cheese, and chicken. The South Island's food bill didn't reset. It just stopped climbing so fast.

This is the hidden cost of inflation: not just the spike, but the permanence of it. Wages might eventually catch up. Interest rates might fall. But the $2,796 increase since 2020 isn't going anywhere. It's the new normal, whether households have adjusted or not.

(Source: Stats NZ, food-price-index-regional)