This study used multi-level modeling in a sample of 952,739 adults across 150 countries to investigate age differences in demographic, psychological, and social predictors of life satisfaction. Based on percentiles of age distribution, the sample was categorized into five age groups (15-24, 25-33, 34-43, 44-57, and ⩾58). The predictors were generally more effective in predicting life satisfaction in older groups (i.e. age ⩾34 years) than in younger groups (i.e. age ⩽33 years). Although the determinants of life satisfaction were generally consistent across the lifespan, the study unraveled differences in the predictive power of some of the predictors across the age groups.
Keywords: Gallup; age; life satisfaction; lifespan; multi-level modeling; well-being.