Among the regular themes in the Australian business press is the claim that we are being outperformed, in economic terms, by New Zealand. I collected a bunch of such claims here, and they were even more prevalent (but hard to find now, being pre-Internet) in the late 1980s. I’m seeing the same theme recurring today (too many repetitions to link).
This is a recurring rather than a continuous theme: there are long periods during which Oz-NZ comparisons are absent from the press. So, if you took the Australian press at face value, it would be reasonable to suppose that Australia was becoming relatively poorer than NZ, not continuously, but in a series of downward steps.
In fact to a close approximation, the reverse is the case. But because market economies are cyclical, there are inevitably brief periods when the NZ economy is on an upswing and Australia in a slowdown or recession. It is only at such times that the business press notices New Zealand’s existence.
A point often made at such times is that net migration from NZ to Australia has slowed to a trickle, usually with the implication that this marks the end of the long term movement. In reality, the cyclical nature of net migration has been a marked feature of movement patterns, ever since the beginning of mass migration westward across the Tasman. The starting point was 1973
Closer Economic Relations Trans-Tasman Travel agreement, which coincided with the beginning of New Zealand’s relative decline. The authority here is Jacques Poot, and this 2009 paper sums up the story.
Interestingly, the flow has continued, unabated though still cyclical, despite the Howard government’s move to exclude Kiwis from welfare payments (arising, IIRC, from a dispute over concerns that NZ’s more liberal immigration policy would provide a ‘backdoor’ path to Australia).