New Zealand's population is increasing by one person every five minutes and 26 seconds, and is forecast to hit 5 million within the next few months. What will the nation look like when it happens,
A new population milestone: We are getting close to 5 million Kiwis
The first million was reached in 1908 and it wasn't until 1952 that it got to 2 million.
READ MORE: Who will be the 5 millionth Kiwi?
Our population currently is estimated to be about 4,960,500, and increases by one person every five minutes and 26 seconds, based on births, deaths and net migration.
According to the population clock, Kiwis have one birth every eight minutes and 43 seconds, a death every 17 minutes and 19 seconds and a net migration gain of a new resident every seven minutes and 25 seconds.
Professor Paul Spoonley, a Massey University sociologist and immigration expert, attributed the growth mainly to government policies in the past two decades, especially around immigration.
"Five million is an important demographic milestone," Spoonley said.
"It does suggest that we need to have a serious debate on population policy given the major changes that are occurring."
Spoonley said issues such as ageing population, declining fertility, the size and role of immigration, regional population stagnation and Auckland's growth needed to be urgently addressed.
Auckland, the country's largest city, is on track to be a city where European residents will make up less than50 per cent of its population.
Spoonley said the city can lay claim to be the most ethnically diverse city of its population size in the world, on a par with Toronto in Canada.
With Auckland's population growing at 2 per cent annually, Spoonley said the city was struggling to cope.
"It is struggling because of the size of the growth and historical deficits - lack of suitable housing stock or an adequate public transport system," Spoonley said.
"The growth has significantly highlighted these past failures in planning and provision."
During the 20th century, natural increases were the main driver behind New Zealand's growing population.
But over the past five years, the dominant factor has been net migration.
A University of Auckland population expert, Associate Professor Dr Ward Friesen, said that since 2000 about 44 per cent of growth was a result of net migration. This has increased to 55 per cent since 2010.
"We have reached the extra million people a little more rapidly than in the past."
Friesen said the reasons for the relatively slow growth between 1973 and 2003 were the end of the baby boom and relatively low rates of net migration.
Over the period, many parts of the country saw more New Zealand citizens moving out than new migrants arriving.
There was an annual migration net loss that started in the mid-1970s, which carried on for many years.
Changes were made to immigration policy in 1987 to increase the role of immigration in the country's population growth after fears the population was growing too slowly.
Friesen said there were concerns that the population might be declining rather than growing.
He too supported the view that a population debate was needed.
"It is legitimate for political parties and others to debate the level of immigration, but most political parties, except NZ First, have tended to support immigration including the target of 40,000 to 50,000 permanent resident migrants."
But he said the debates so far about net migration had "not been fully informed" and that it had to go beyond the discussion of net migration numbers.
"The impacts of less net migration loss of NZ citizens is not the same as increase of new permanent migrants," Friesen said.
It hasn't been a case of an influx of new permanent migrants that led to the population reaching 5 million in record time.
Rather, it was because of a lower net loss of NZ citizens, Friesen said, and the increases in work permit migrants and international students.
"The impacts of less net migration loss of NZ citizens is not the same as increase of new permanent migrants," Friesen said.
"Also the increase in temporary workers is largely driven by labour demands and has different implications again than permanent residency changes or changes in the migration patterns."
About a fifth of the population, or more than a million people born overseas, now live in New Zealand. Hundreds of thousands of New Zealand-born people live overseas, most of them in Australia.
"The challenges that face us are not only about inclusive attitudes and policies to those who will be in NZ long-term, but also to many who are 'temporary migrants' who may be here for considerable periods," Friesen added.
Over the next four days, the Herald will speak to New Zealanders on their recollection of what happened on the milestone years.
Tomorrow, we look at the years when the first two round numbers with six zeroes were reached.
A 96-year-old great grandmother, who grew up in Southland, talks about the years before television and the radio being her "window" to the world.
Then a 59-year-old Auckland businessman remembers the first colour television broadcast in the year the population hit 3 million.
And a Ponsonby event planner talks about 2003, when the population hit 4 million, as a year of change, and how decriminalisation of sex work here made world headlines.
The number of New Zealanders is growing fast, and on the final day of the series we talk to experts and Kiwis about what the country would be like as we move towards the next milestone.
According to Statistics New Zealand, if migration remained at historically high levels, the 6 million population mark could be reached as soon as the 2030s.
But the latest 2016-base projections indicated that it would probably be the mid-2040s that we reach the next million milestone.
THE SERIES
Tomorrow: Hitting 2 million
Wednesday: Hitting 3 million
Thursday: Hitting 4 million
Friday: What NZ might be like at 6 million