New Zealand's annual net migration slowed in March as continued high immigration was offset by more Kiwis and non-citizens leaving.

Annual net migration was at 68,000 in the year to March, from 71,900 in the year to March 2017, Statistics New Zealand said.

Monthly net migration has been in flux this year, having risen to a seven-month high of 6,210 in January, causing market watchers to question whether the trend of declining net migration had reversed or whether the month was an anomaly. The figure dropped back to 4,970 in February, lower than any month in 2017, while in March, monthly net migration recovered to 5,480.

There was a 0.1 percent drop in non-New Zealanders immigrating in the March year to 98,800, compared to the February year, and a 2 percent lift in the number of non-New Zealanders leaving to 29,700, leading to overall net migration of non-New Zealanders of 69,100. A net 1,100 Kiwis left in the latest year, reducing total net migration to 68,000.

"More non-New Zealand citizens are leaving," Stats NZ population insights senior manager Brooke Theyers said. "But there are just as many migrants arriving as a year ago."

New Zealand has been experiencing record levels of net migration in recent years, which made rising immigration a key election issue as it strains the country's infrastructure and is blamed for inflating property markets. Net migration peaked at 72,400 in the July 2017 year.

"Smoothing through month-to-month volatility, net migration has been easing back since mid-2017," said Westpac senior economist Satish Ranchhod in a note.

"Looking forward, we expect that migration will continue to ease back over the next few years. Much of the increase in migration in recent years was due to people arriving on temporary work and student visas. We are now seeing many of those earlier arrivals departing. We expect that this will continue for some time yet."

Increasing numbers of migrants came on work visas in the latest year, up 6 percent to 46,300, with residence visa numbers down 13 percent to 15,000 and student visas dropping 0.1 percent to 23,800. China continued to be the biggest source of migrants on residence visas, though that dipped 17 percent to 2,800 in the year, while the United Kingdom was the biggest source of work-visa migrants, up 1.1 percent to 7,400.

Despite the drop in residence visas granted, Chinese migration remained the largest on a net basis, with 8,500 of net arrivals coming from China, though that was down 16 percent on a year earlier. India was the second-largest source at a net 6,900, though Indian net migration was also down 14 percent from a year earlier.

Short-term visitor arrivals, which include tourists, people visiting family and friends and people travelling for work, reached 3.8 million in the March year, up 8 percent from a year earlier.

(Source: NZ Herald, Business Desk)