The Green Party is critical of "excessive" profits made by big Australian banks in New Zealand since the global financial crisis while other industries' profits have slumped.
Research from the Parliamentary Library shows the big four trading banks - ANZ, BNZ, ASB and Westpac - collectively made more money in the four years following the global financial crisis than the four years preceding it.
Their 2008-2011 combined net profit before tax was $14.4 billion - $337 million more than in the 2004-2007 period.
However, the banks' profits took a $2.2b hit after settling a dispute over structured financial transactions with Inland Revenue in 2009.
All New Zealand industries, by comparison, took a 14.9 per cent hit - falling from a before tax surplus of $214.6b in 2004-2007 to $182.7b in 2008-2011.
Green Party co-leader Russel Norman says the banks' profits, teamed with the high level of foreign ownership in the banking sector, are causing long-term damage to the economy.
He accused outgoing Reserve Bank governor Alan Bollard of complacency over the issue, after Dr Bollard last week admitted bank profits in New Zealand are "higher than in most other banking systems".
"His complacency is astounding, for the excess profits banks are making are simply damaging the rest of the New Zealand economy and contributing to our number one problem - a high and persistent current account deficit," Dr Norman said.
He says incoming Reserve Bank governor Graeme Wheeler will face a challenge of promoting competitive behaviour in the banking sector "so that the rest of the economy isn't suffering due to excessive profit-taking".
"The challenge for the Government is to build up our New Zealand-owned banks to stem the flow of profits offshore."
New Zealand-owned banks make up just six per cent of the sector.
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