Age-Income Profiles in New Zealand: New Estimates Based on Administrative Data

Abstract

This paper uses a new longitudinal dataset, containing information about the incomes of New Zealand individuals, to examine the form of cohort age-income profiles. A model of the variation in mean log-earnings with age, allowing for quadratic age and linear time effect, is estimated separately for males and females, along with a range of other demographic groups. An 'overtaking' property, whereby more recent cohorts have higher real income than older cohorts, at comparable ages, are found in all cases. Cubic profiles of the variation in the variance of log-income with age are also estimated. Examples of the projected changing distribution of income with age are given, for various cohorts aged 20 in 2020.