Speaking to the Otago Daily Times after launching his state of the economy briefing, Dr Nana said Berl was often criticised for being negative in its comments.
Although he was more than happy to acknowledge the current situation of the economy, he warned caution was required.
''We are not using the dividends of the rock star economy to build a platform for the future.''
Government debt was well under control by New Zealand's historical standards. It was the debt to income ratio of Kiwis which needed addressing, he said.
Latest Reserve Bank data indicated household sector debt was 165% of disposable income, topping earlier pre-Global Financial Crisis highs.
And with credit to the housing (mortgage) sector increasing by 9% in the year to July, on top of the 6% increase the year earlier, there were no signs of the debt stabilising.
New Zealand had experienced strong employment growth and declining unemployment, an improving external account on the back of robust export income shored up by tourism activity, recovering dairy prices, the government books back in black, tax cuts being touted, inflation well and truly tamed and positive business and consumer confidence, Dr Nana said.
''There would seem little to be concerned about. But there is a nagging feeling that is difficult to shake for many.''
The Government last week announced a surplus of $1.8billion for the year ended June and Prime Minister John Key and Finance Minister Bill English hinted tax cuts would be announced before next year's general election.
Dr Nana questioned the wisdom of using the money for tax cuts when the Government should be pushing investment away from housing and towards business, jobs and research and development.
''If we're serious about enjoying the dividends of the economy, we shouldn't accept child poverty as something we have to put up with. Focusing on lifting low wages and investing in education and schools are the sort of things we should be spending money on rather than frittering it away.''
The Government had to take the lead role in turning the economy towards investment in ''real dividends'' for New Zealand, he said. Dr Nana suggested putting some regulations around the banking system to encourage funds going towards business development.
The global economy remained precarious, with the impact of Brexit still ahead. When the International Monetary Fund pointed to unresolved legacy issues in the European banking system, and continued reliance on credit as a driver of growth was heightening risk of an eventual disruptive adjustment in China, the ground felt less secure, he said.
But there were also domestically sourced concerns, primarily around the asset price bubble threatening the stability of the financial system. Also, some considered the drivers of the current growth to be transitory rather than sustainable.
The tourism surge was not transitory and was set to remain a feature of the New Zealand economic scene. Whether the sector and the country had the capacity, or was prepared to make the necessary investments, to sustain and profit from the surge remained moot, Dr Nana said.
Historically, large migration net inflows were also a considerable driver of current growth but elements, in particular students from some markets, were likely to be transitory.
Another driver of current growth was construction sector activity, residential building in particular.
There were no signs construction activity was transitory as house building caught up from several years of a slump.
The missing element in the growth story was the merchandise export sector. Although wine, kiwifruit and fish were some of the success stories, the overall picture was of a sector treading water.
''Our rock star situation clearly provides us with opportunities to tackle the long-term imbalances present in the New Zealand economy. However, the prominence of tax cuts in the immediate debate signs little desire to confront these fundamental challenges.''
