New Zealand's estimated population grew by 1.2 per cent to 4.37 million in the year to June 30, an increase of 51,900, Statistics New Zealand said today.

The growth was due to 35,400 more births than deaths and net migration of 16,500.

"Natural increase was 35,400, up 1000 from the June 2009 year, accounting for about two-thirds of population growth in the June 2010 year," population statistics manager Bridget Hamilton-Seymour said.

"Permanent and long-term arrivals exceeded departures by 16,500 in the latest year, compared with a net migration gain of 12,500 in the June 2009 year".

Half the male population was over 35.5 years of age and half of females over 37.6 - an increase of 2 years for males and 2.5 for females over the last 10 years, chief statistician Geoff Bascand said, indicating New Zealand's ageing population.

At June, there were 96 males for every 100 females.

(Source NZPA)