Headlines scream about Kiwis raiding their retirement savings to cover grocery bills (as reported by RNZ, February 2026). Financial pressure is real, widespread, and measurable across New Zealand. But in Rotorua, the food price data tells a story nobody's explaining: the numbers just fell off a cliff.

In 2013, Rotorua's food price index sat at 15,317. Twelve months later? 7,683 (Source: Stats NZ, food-price-index-detailed). That's not a drop. That's half the index disappearing overnight.

This isn't about food getting cheaper — it's about how Stats NZ measures it. Something changed in the methodology between 2013 and 2014, and Rotorua's data captures that shift in stark terms. The index didn't halve because groceries suddenly became affordable. It halved because the baseline changed.

Here's why this matters right now. When people talk about cost-of-living pressure — when they point to food prices driving hardship applications through the roof — they're using data like this. But if the measurement system shifts halfway through, comparisons become meaningless. You can't track a crisis using a ruler that keeps changing length.

Look at the trajectory leading up to 2014. Rotorua's index climbed steadily: 14,492 in 2010, 15,309 in 2011, holding around 15,300 through 2013. Then the methodological break. After 2014, you're comparing apples to oranges — literally, in some cases, since food price indices track specific products.

This isn't unique to Rotorua. It's a window into how economic data gets collected, revised, and rebased. But Rotorua's numbers make the break visible in a way other regions don't. The 50% drop in a single year is a flashing light on the dashboard, signalling that something fundamental shifted in the measurement.

For readers trying to understand whether their grocery bills are historically high or just feel that way, this matters. You need consistent data to make that call. When the index rebases — when Stats NZ updates its methodology, as statistical agencies do periodically to stay relevant — it creates a discontinuity. The numbers before and after aren't directly comparable without adjustment.

So yes, KiwiSaver hardship applications are spiking. Yes, households are under financial pressure. But when you're trying to quantify that pressure using food price data, know this: the historical comparisons only work if you account for methodological changes. Rotorua's 2014 data is the clearest evidence we have that something shifted in how these numbers get recorded.

The lesson? Be sceptical of any analysis that draws a straight line through data spanning this period. The line isn't straight. It bends in 2014, and unless you acknowledge that bend, you're not measuring reality — you're measuring measurement.