Affordability in New Zealand

This website is produced by MRCagney as a public education tool illustrating the multifactorial nature of affordability and how big a role geography plays in it. Our analysis is inspired in part by the article "Housing and Transport Expenditure: Socio-spatial Indicators of Affordability in Auckland" by K. Mattingly and J. Morrissey [MaMo2014] and is updated at the end of every calendar quarter.

Data and Methodology

• The areas displayed in each map are 2019 Statistical Area 2 (SA2) boundaries defined by Stats NZ.
• The median gross annual incomes of waged Aucklanders, Wellingtonians, etc. come from the Statistics NZ 2020-06 income data. Taxes are then subtracted using the PAYE calculator to yield median net annual incomes.
• Rents come from the Ministry of Business, Innovation and Employment (MBIE) rental bond data. We use median rents taken from the last six months up to 2024-09-30.
• Commute distances and times were computed as follows. For each rental area we chose a sample point, namely the centroid of all its address points; see Auckland sample points, Canterbury sample points, Wellington sample points. Then for each ordered pair of sample points and each mode of travel, we used the Targomo API to compute the distance and duration of the quickest path through the street network between the points departing 08:00 Monday 2021-03-01. These durations include Targomo's estimated rush hour delays for cars.
• Commute costs per kilometer come from [MaMo2014, Table 2] and are (walking, bicycling, driving) = (0, 0, $0.274). Public transport costs were estimated from card fares for journeys between rental area sample points using the Auckland Transport journey planner, the Wellington Metlink journey planner, and the Christchurch Metro fare zones .
• Car ownership cost per car per year comes from [MaMo2014, Table 3] and is $2228.

Frequently Asked Questions

Why are there so many n/a values on the maps?

That's mostly because we are using only the last six months of rental bond data from MBIE, and many rental areas haven't had new bonds lodged then. We could remedy that by using older data for those areas, say from the last 1–2 years, but that's probably more misleading than informative.

So what is affordable, that is, what fraction of my net income should I be spending on rent and commute costs?

That depends on your financial targets. For example, if you want to live frugally like Mr. Money Mustache, then you want to save at least 65% of your net income, leaving at most 35% for expenses. Some of that needs to go to food, clothing, healthcare, etc., leaving roughly 20% of net income for rent and commutes.

Why not include other costs in the app, such as food, power, and Internet?

We want to emphasize the spatial nature of affordability and balance accuracy with simplicity, informing but not overwhelming the user. So we include the dominant and most spatially variable costs and exclude the rest, such as food, power, and internet.

Feedback?

This project is a work in progress and your feedback can help make it better. Email us.