Constructing a Longitudinal Database for the Analysis of Individual Incomes in New Zealand

Abstract

This paper describes the construction of a unique longitudinal individual-level dataset that allows the dynamics of individual incomes in New Zealand to be examined. The data are obtained from the New Zealand Integrated Data Infrastructure, and cover approximately 393,874 taxpayers, for whom a range of information including, but not limited to, taxable income, gender, ethnicity, education level and location have been compiled. The availability of suitable data has previously been a constraint on income dynamics research. The present data construction exercise allows a more extensive analysis of individual income inequality and mobility than has previously been possible.