Newly published accounts show the tax take is stronger than expected, boosting the Government accounts.

Higher than expected tax revenue has the Government's accounts in better than expected shape.

On Tuesday the Treasury released the financial statements of the New Zealand Government for the six months to December 31, which showed an operating balance before gains and losses of $1.1 billion.

This was $779 million better than Treasury was expecting at the time that Finance Minister Grant Robertson delivered the half year economic and fiscal update in early December.

Crown expenses were marginally higher than forecast, but this was more than offset by stronger tax revenue.

READ MORE: Debt tracking below expectations

While the monthly accounts often show fluctuations, in recent months the books have been consistently healthier than expected, and Treasury has hinted that this may continue.

Chief government accountant Paul Helm said source deductions - such income tax - was around $300 million higher than anticipated, while GST was $200m ahead of forecast.

"Some of this variance can be expected to remain until year end," Helm said in a statement.

Net debt was $64.5 billion at the end of 2017, about $500m lower than forecast.

"This variance was mainly due to higher circulating currency and higher than forecast valuation gains."

Robertson said the results "chime with the evidence we've been hearing through recent consumer, employee and business confidence surveys".

At the end of 2017 unemployment fell to 4.5 per cent, the lowest in 9 years, while surveys showed strong job advertisement listings and consumer confidence.

While headline business confidence has plunged, Robertson's office has focused on the 'own activity' measures in recent surveys - the confidence of businesses about their own activity - which has remained strong.

"We've seen consumer confidence improve over the past month, while businesses' confidence in their own activity – which is more closely correlated to economic growth than headline business confidence – has also been positive."

Meanwhile, ratings agency Moody's has reiterated its Aaa rating of New Zealand - the highest possible.

"New Zealand's credit profile reflects its very high economic resilience, very strong institutions and policy effectiveness and a strong fiscal position compared to peers," analyst Matthew Circosta wrote.

"These credit features mitigate external and domestic vulnerabilities related to high reliance on external financing and elevated household debt."