You know the ones – projections that the proportion of people over 60 is set to nearly double by 2050, or that the “old-age dependency ratio” is skyrocketing. Here in New Zealand, we’re certainly part of this global trend. Statistics New Zealand data shows that in 2023, around 828,600 people were aged 65 and over, making up 16.6% of our population.
This is projected to hit 1 million people by 2028 and could reach 1.9 million (or 28.2% of the population) by 2073! It’s easy to feel like we’re heading for some sort of demographic cliff.
But what if these numbers, as eye-opening as they are, aren’t telling the whole story? What if the very definition of “old age” we’re using is outdated?
That’s the fascinating question raised by Sarah O’Connor in a recent article in The Financial Times, where she suggests that how long someone has been alive – their chronological age – might actually be a pretty poor yardstick for judging who is truly “old.”
Why Chronological Age Falls Short
Think about it: what does simply knowing someone is, say, 65 years old really tell you? Not much, beyond the number of birthdays they’ve celebrated. Policymakers often lean on chronological age as a shortcut, a proxy for concerns like how many people will need health or social care, or the economic impact of more retirees and fewer workers.
The problem, as economists Rainer Kotschy, David Bloom, and Andrew Scott argue in their research, is that this shortcut is “at best incomplete and at worst misleading.” Here’s why:
A New Perspective on “Old”
If traditional age markers aren’t cutting it, what’s a better alternative? Researchers Warren Sanderson and Sergei Scherbov, pioneers in this field, offer an intriguing idea: defining the onset of “old age” not by how many years you’ve lived, but by how many years you realistically have left to live. Specifically, they propose defining “old” as the point when you have 15 years of life expectancy remaining.
Applying this “remaining life expectancy” lens paints a very different picture. In the UK, for example, while the number of people over 65 grew between 1981 and 2017, the number of people with less than 15 years of life expectancy actually fell. It makes those “scary statistics” look less like an inevitable burden and more like a manageable shift.
There’s even talk of “biological age” – using metrics like blood proteins to determine a person’s physical age, which could one day influence policies like state pension ages. While intriguing, the idea of two people the same chronological age but receiving pensions at different times due to biological differences highlights the complexities of such approaches.
Ultimately, there’s no single perfect way to measure population aging. But the real takeaway from this discussion is that our definition of “old” isn’t fixed in stone. It’s far more flexible and dynamic than we often assume. By shifting our perspective beyond a simple number, we can start to see the challenges of an aging population not as an unavoidable destiny, but as an opportunity for innovative thinking and adaptable policies that truly reflect the diverse experiences and capabilities of older New Zealanders.
Copyright Notice:
This summary is based on The Financial Times article “Age is more than a number when it comes to policy” by Sarah O’Connor https://www.ft.com/ content/7b2113fe-d5a8-4c75-b0ce-ccd9e3dcbcab, and includes New Zealand specific data from official sources such as Statistics New Zealand (Stats NZ), Macrotrends, Te Ara Ahunga Ora Retirement Commission, and Infometrics.
Original article copyright The Financial Times Limited 2025. All rights reserved.
