More people are leaving New Zealand than arriving with many citizens leaving for Australia, the latest figures shows.

Departures exceeded arrivals by 600 people last month which means that net losses have been recorded in 10 of the 11 months since the February 2011 earthquake in Christchurch, the data from Statistics New Zealand show.

Unadjusted figures showed 700 more departures of New Zealand citizens compared with January 2011, including 900 more to Australia. There were also 400 fewer arrivals of New Zealand citizens.

New Zealand had a net loss of 3,100 migrants in the January 2012 year. This is the largest net loss since the August 2001. In the January 2012 year, there was a net loss of 38,100 people to Australia, the highest ever recorded. There were 51,900 departures to Australia, offset by 13,800 arrivals from Australia. In both directions, most migrants were New Zealand citizens.

There were net gains of migrants from most other countries, led by the United Kingdom with 5,400, India with 4,900, and China with 4,800 in the January 2012 year.

There was a record number of international passengers to and from New Zealand in January 2012, with 1,002 million arriving, the first time this number has exceeded a million in any month.

In January 2012, there were 266,800 overseas visitor arrivals, up less than 1% from January 2011. The increase in visitors was mainly due to 7,000 more arrivals to visit friends and relatives. Holiday arrivals were down 4,200 and arrivals for conferences and conventions were down 800.

By country, there were more visitors from China and Australia, but fewer from the United Kingdom and Japan. The number of visitors from China, 23,300, was the highest recorded for any month.

Population Indicators project manager Susan Hollows said that travel from China in January was influenced by the earlier timing of Chinese New Year which was 23 January. In 2010 and 2011, Chinese New Year was in February.

Visitor arrivals in the January 2012 year were 2.603 million, up 3% from 2011.

New Zealand residents took 129,100 trips in January 2012, up 10% from January 2011. They took more trips to Australia, the United States, and Fiji. In the January 2012 year, New Zealand residents took 2.104 million overseas trips, up 3% from 2011.