http://igps.victoria.ac.nz/WelfareWorkingGroup/Downloads/Wor...
Key takeaways:
"An income of $300 per week is just over the average (mean) benefit income – therefore a plausible minimum income. However, paying a guaranteed income of $300 per week to every New Zealander aged 16 years and over, excluding superannuitants, comes at considerable fiscal cost. The fiscal cost of the GMI proposed in the first model (Model 1) is $44.5 billion (including the cost of all social transfers – in particular, New Zealand Superannuation payments, would cost $55.5 billion), requiring a flat personal tax rate of approximately 45.4%. Note that this tax rate and the others considered below are cost-neutral – not fiscally neutral – as personal taxes currently raise approximately $6 billion in excess of current social assistance costs."
"Although the Gini coefficient improves under all models, many beneficiaries (including the disabled, carers and sole parents) currently receive more than $300 per week and would be made financially worse off under a GMI scheme. Therefore the GMIs considered could distribute money away from those most in need of government assistance and toward those who have choices and opportunities but choose not to work."