This paper examines the optimal direction of marginal income tax reform in the context of New Zealand, which recently reduced its top marginal income tax rate to one of the lowest in the OECD. A behavioural microsimulation model is used, in which social welfare functions are defined in terms of...

This paper examines estimation of the elasticity of taxable income using instrumental variable regression methods. It is argued that the ‘standard instrument' for the net-of-tax rate − the rate that would be applicable post-reform but with unchanged income levels − is unsatisfactory in...

This paper examines the extent to which projected aggregate tax revenue changes, association with population ageing over the next 50 years, can be expected to finance expected increases in social welfare expenditures. Projections from two separate models, dealing with social expenditures and...