The Sustainable Net Benefit Index (SNBI) is an alternative indicator for GDP, resembling ISEW and GPI. SNBI is defined by the difference between 'uncancelled' benefits of economic activity (e.g. services from volunteer work; distribution of income) and the 'uncancelled' costs of economy activity (such as loss of natural capital services). It directly compares the benefits and costs of a growing macroeconomy. Developed by Lawn and Sanders in 1999.