How lockdown affected your area

Just who of us was on the move and who stayed put during lockdown level four? Stuff’s Andy Fyers and Felippe Rodrigues analysed cellphone tower data to find out.

New Zealand’s cities ground to a halt during lockdown, with mobility down by as much as 60 per cent in some places. Meanwhile, life was much closer to normal in many rural areas as essential workers stayed on the job.

A Stuff analysis of cellphone tower data shows how the lockdown affected different parts of New Zealand in different ways.

Overall, New Zealanders reduced their movement by about half during the level four lockdown compared with a normal pre-lockdown week. On average, there was 46 per cent less mobility throughout the country.

But the reductions in mobility varied significantly in different places. In Wellington City, mobility was down 62 per cent, the biggest drop of anywhere. In some rural districts, movement reduced by less than 20 per cent.

This is not necessarily a reflection of Wellingtonians being more stringent in obeying lockdown rules than rural communities, as each is compared to a normal week in their own area.

Wellington, with its thousands of workers commuting in from the wider region, has a much busier normal week than O¯ torohanga, for example. In addition, rural areas contain many essential workers who continued to work as normal.

So comparisons between places are fraught. But the data nonetheless provides an insight into how the disruption of level four was felt around the country.

It comes from Data Ventures, an arm of Stats NZ, and is based on cellphone tower data which takes a snapshot of the population in each neighbourhood in New Zealand at hourly periods. The data is only an aggregate count and does not track individuals.

Other parts of the Wellington region, such as Porirua, Upper

Hutt and Lower Hutt, also saw reductions of more than 50 per cent in mobility. In the Taranaki region, New Plymouth and the Stratford district were also down more than half, as were Tauranga, Napier and Taupo¯ .

In Auckland there was an overall reduction of 46 per cent, Dunedin was down 42 per cent, and Hamilton and Christchurch

48 per cent, further illustrating how urban areas were best able to reduce their movement compared with the prelockdown.

On a national level the data also suggests that Kiwis may have let up slightly in the final week of lockdown. In the first seven days of level four, mobility was down 48 per cent compared with a normal pre-lockdown week. For the seven days to April

26 (the second-to-last day of level four), movement was down 43 per cent.

The Government did give approval for people to enter business premises, schools and other workplaces in the final week to prepare. So this may account for some or all of the difference.

The mobility measurement used for this analysis is based on a methodology developed by Data Ventures. It looks at how much neighbourhood populations vary each day. The variations are then aggregated by district and city council and compared to the variation on a normal day.

If the neighbourhood populations vary a lot within an area that indicates people are moving around – more mobility. If they are relatively static throughout the day that indicates people are staying put – less mobility.