The interest income earned is called seigniorage income, and in New Zealand it amounts to about $ million each year (a currency on issue of a little over $ billion, invested in government securities to yield somewhat over 6 per cent per annum).
Other leading economists find that the relationship between economic development and natural resources is more complex; many countries become poorer after discovering abundant natural resources, while others become wealthier. Sachs and Warner conclude that the quality of the institutional framework is decisive.