The 2025 Taskforce faces a huge challenge to achieve its aim of closing the income gap between New Zealand and Australia over the next 16 years.

The taskforce, chaired by former National Party leader Don Brash, estimates that closing the income gap would require New Zealand's economy to grow 1.8 per cent faster per annum than Australia's until 2025.

According to the taskforce website, Australia's per capita GDP currently sits at around NZ$32,000 and is estimated to reach almost NZ$40,000 by 2025.

If New Zealand's per capita baseline GDP - currently around NZ$24,000 - continued to grow at its current rate it would reach only NZ$30,000 by 2025.

The increased growth rate the taskforce envisages would see New Zealand and Australia having equal per capita GDPs by 2025.

Australian workers also enjoy average earnings 30.5 per cent higher than their Kiwi counterparts. And with higher earnings come better standards of living.

According to the Australian Bureau of Statistics figures, their average incomes for 2008-2009 are as follows (in NZ $):

-Full time adult ordinary time earnings - $77,845.85

-Full time adult total earnings - $81,034.03

-All employees - $60,509.90

According to statistics NZ the 2009 average yearly Kiwi income from all employees is NZ$35,360.

The annual Human Development Index, used by the United Nations Development Programme for its development reports, listed New Zealand at number 20 out of the 179 countries in its 2008 index.

In comparison, Australia came it at number four - indicating a higher level of "development" and better living standards.

In a speech delivered at AUT in July Brash said the current state of New Zealand's economy was "extremely serious".

"If we continue to languish in the bottom third of OECD countries - even worse if we continue to slide backwards - the things which have made New Zealand a pleasant place to live will gradually disappear," said Brash.

He added that New Zealand might find itself unable to afford the healthcare and standards of education that "richer countries take for granted" if its economy continued to underperform.

Taskforce member and Electricity Commission chair David Caygill said he did not except that New Zealanders should "settle for or deserve less" than workers living in other countries.

"Australia's our closest neighbour and if New Zealanders are heading there primarily because the opportunities are greater it means the rest of us are losing out."

Caygill said it was feasible that New Zealand's economy could catch up with Australia's by 2025.

"It's not going to be easy, but its desirable and it's possible."

However, Auckland University economics professor Tim Hazledine said it was unlikely that the taskforce would achieve its aims.

"[Members of the 2025 Taskforce] are big fans of the deregulation, so called, that we've been through, they're not going to say we made a huge mistake with Rogernomics and we should have adopted a gradualist, more business friendly policy like the Australians did."

Hazledine said New Zealand should stop measuring its GDP and simply enter a currency union with Australia.

"The idea of having an ANZAC dollar wouldn't be a panacea but it would be good for doing business in New Zealand, because our largest trading partner would then be in the same currency area."