The increasing gap between the Australian and New Zealand interest rates is indicative of the comparative growth strength of the economies.
Australia did not go into recession during the global financial crisis as it only recorded one quarter of negative growth.

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The benefits of riding through that time are becoming evident in the Australian economy now as it appears to be carrying on in a 'business as usual' fashion.
The strength of the Australian economy is creating some investment opportunities for New Zealanders and this is particularly the case with the growing gap between the two country's interest rates.