I've divided this request into a minimal data set (needed urgently to inform public debate around our ongoing housing crisis) and an ideal data set (a stretch goal for deeper research). 1. Minimal data set For every year since 1982, over residential properties in New Zealand: - what was the average* land value (unimproved value) - what was the average* capital value (land + improvements) *mean, median, or both depending on availability 2. Ideal data set Grouping variables: - Year (since 1970) - Locality (territorial authority broken down by suburb or rural area) - Asset class (e.g. residential, commercial, industrial, Māori land, conservation land, etc) Measures: - Total land area - Total land value - Total capital value - Number of property titles - Median land value - Median capital value

Finding root causes and solutions to the ongoing housing crisis, the number one policy issue in New Zealand over recent decades.

Informing public debate and expert analysis of trends in house prices.

Distinguishing the two main components of property prices, the price of land and the price of improving the land (e.g. building a house).

Providing historical data that goes back long enough to cover periods of time with different policy regimes for example, taxation and immigration.

The ideal data set would feed into analysis of the likely effects of different policy ideas, e.g. rating different asset classes differently.

Localised data could be used to better understand patterns in property ownership across different communities. It could, for example, be correlated with Census data on renting to help understand the effects of historical or proposed policy regimes on renters vs owner-occupiers.