The belief that high income is associated with good mood is widespread but mostly illusory. People with above-average income are relatively satisfied with their lives but are barely happier than others in moment-to-moment experience, tend to be more tense, and do not spend more time in particularly enjoyable activities. Moreover, the effect of income on life satisfaction seems to be transient. We argue that people exaggerate the contribution of income to happiness because they focus, in part, on conventional achievements when evaluating their life or the lives of others.
Kahneman, D., Krueger, A. B., Schkade, D., Schwarz, N., &Stone, A. A. (2006). Would you be happier if you were richer? A focusing illusion. science, 312(5782), 1908-1910.
DOI: 10.1126/science.1129688