The Rugby World Cup and a rise in manufacturing production have bolstered economic growth in recent months.
Gross domestic product (GDP) data shows that the economy grew 0.8% in the three months to the end of September - the fastest quarterly rate of growth in nearly two years - and 1.3% in the year to the end of September.
The head of Asia-Pacific research for TD Securities in Singapore, Annette Beacher, says the Rugby World Cup clearly provided a one-off boost, but it was not the only contributor.
The biggest surprise, she says, is that manufacturing had "quite a strong quarter". The sector rose 2.3%, mainly because it produced more food, beverages and tobacco.
Retail, accommodation and restaurants were the next biggest contributors to the rise, recording their best quarter since the current set of records began in 1987.
Ms Beacher says growth will slow as households pay back debt and spend cautiously because of worries about the global economy.
Radio New Zealand's economics correspondent says GDP has now risen in nine of the past 10 quarters, but is still below its peak at the end of 2007.