Population growth, boosted by a record net migration gain, explains about half of the strong economic growth recorded last year.
Gross domestic product rose 0.8 per cent in the December quarter, in line with market expectations, to be 3.5 per cent higher than a year earlier.
On a per capita basis GDP growth was 1.8 per cent last year, up from 1.4 per cent in 2013.
The rest of the 3.5 per cent annual GDP growth reflected a 1.7 per cent rise in the population, two-thirds of which came from a net inflow of 50,900 permanent and long-term migrants.
Over the past four years - roughly the period of recovery from the recession - GDP growth per capita has averaged 1.5 per cent per annum.
National income per capita has grown at twice that pace over the same period, however, the difference largely reflecting strong gains in the terms of trade - relative prices for the kinds of things New Zealand exports versus the kinds of things it imports - which peaked last June at the most favourable level for 40 years.
But since then the terms of trade has declined more than 6 per cent and has yet to fully reflect the decline in dairy prices.
In the latest year national income per capita was flat, reflecting both a retreat in the terms of trade and a larger net investment income deficit.
"Since it strips out price effects, real GDP is not directly affected by changes in the terms of trade," Capital Economics' chief economist for Australia and New Zealand, Paul Dales, said.
"But it is indirectly affected as lower export revenues tend to eventually filter through into weaker investment, employment and consumption growth."
There were some signs of that in the latest data.
Gross fixed capital formation, the broadest measure of investment sending, rose just 0.2 per cent in the December quarter, though it was up 7.5 per cent for the year.
The slowdown largely reflected less spending on non-residential buildings and transport equipment. Investment in plant, machinery and equipment grew 1.6 per cent and intangibles 5.9 per cent. Population growth as well as the Christchurch rebuild underpinned the quarter's 5.2 per cent growth in spending on residential building, making 16.3 per cent for the year.
Private consumption spending also slowed. It rose 0.6 per cent in the December quarter but was 3.7 per cent for the year. It was boosted by a surge in spending by international visitors, up 15 per cent in the quarter, 22 per cent higher than a year earlier.
"Visitor arrivals have been trending higher for some time, led by strong growth in Chinese tourists and a recovery in US tourist numbers," ASB economist Jane Turner said. "We expect these encouraging trends to continue, in part supported by continued improvement in household demand in the US and China."
Tourism also boosted services exports, which rose 8.8 per cent in the quarter, and contributed to a 6.1 per cent rise in export volumes overall, which outstripped the quarter's 3 per cent rise in imports.
Goods exports rose 4.6 per cent in the quarter in volume terms, underpinned by close to a 10 per cent rise in non-primary exports, with primary exports up close to 2 per cent, ANZ economist Mark Smith said. "Both are likely to unwind somewhat in 2015."
The December quarter data suggested the economy was in good nick heading into 2015, he said. But he expects some softening given the pending hit from drought and services exports shifting down a gear after the current boost from the Cricket World Cup.
Westpac economists Michael Gordon said growth of 0.8 per cent a quarter, or more than 3 per cent annually, would be above anyone's estimate of the economy's long-run potential growth rate. "A continuation of this pace of growth would eventually put a strain on the nation's resources and, one could reasonably expect, lead to higher wage and price inflation."