ABSTRACT
Another way of studying the effects of income on happiness is to study the relation between average incomes and average happiness for whole countries. There have been a number of studies like this, using up to 55 countries. All have found a strong correlation of about .60 (Diener and Biswas-Diener, 2000). Comparing the richest and poorest nations there is a difference of about 7 out of 30 units of the Satisfaction With Life Scale, a quarter of the whole scale. Some studies found a levelling off part of the way up the income scale, but other studies did not. Diener et al. (1995) did not find any levelling off, and they found that per capita GDP and average purchasing power correlated with satisfaction at .33 and .37 with basic need fulfilment held constant.
