Everyone knows groceries cost more than they used to. But most people don't realise just how much the ground has shifted beneath their feet over five decades.

In 1975, the average South Island household spent $645 on food for the year. That works out to about $12.40 a week. Fast forward to 2024, and that same household is spending $15,305 annually. That's $294 a week.

The trajectory has been relentless. Even accounting for inflation, the increase is staggering. But what really stands out is the acceleration in recent years. Between 2020 and 2024, the South Island's annual food bill climbed from $12,509 to $15,305. That's a jump of $2,796 in just four years.

To put that in perspective: the cost increase over those four years represents more than four times what South Islanders spent on food for an entire year back in 1975. (Source: Stats NZ, food-price-index-regional)

The pattern is worth examining closely. From 2020 to 2021, the increase was modest: $257. Then came 2022, when prices jumped $969 in a single year. By 2023, another $1,329 was tacked on. The pace slowed slightly in 2024, with a $241 rise, but the damage was done.

This isn't an abstract economic indicator. It's the difference between affording fresh vegetables and reaching for cheaper, less nutritious options. It's the reason families are stretching dinner leftovers into lunch the next day. It's why KiwiSaver balances are being raided and credit card debt is climbing.

For a South Island family on a tight budget, that $2,796 increase since 2020 represents weeks of wages. It's a new washing machine they can't afford to replace. It's the holiday they used to take but don't anymore. It's the slow erosion of living standards that no single grocery shop reveals, but fifty years of data makes impossible to ignore.

The South Island's story isn't unique. But the numbers here tell the tale with brutal clarity: food costs aren't just rising. They're accelerating. And for households already stretched thin, there's no sign of relief.