Income moderates changes in big-five personality traits across eighteen years

The role of income in adult personality change remains poorly understood. Using latent growth modeling, we performed exploratory analyses of how longitudinal trajectories of change in personal income and the Big Five personality traits would be related. We examined 4234 participants (2149 Males, 2085 Females; MT1age = 46.42, SDT1age = 13.36, age range at T1: 20–74 years) across three time points spanning 18 years using data from the Midlife in the United States study. Results indicated that starting levels of income moderated changes in four personality traits. Specifically, income moderated the slopes of openness to experience, extraversion, agreeableness, and neuroticism, such that for high-income individuals, openness to experience, extraversion, and agreeableness were less likely to decline and more likely to either increase or remain stable over time, while neuroticism was less likely to increase and more likely to remain stable over time. Conversely, personality traits were weaker predictors of income change as slopes of income were not moderated by starting levels of any of the personality traits. Moreover, changes in income were not correlated with changes in any of the personality traits. The findings suggest that individual differences in income could potentially explain diverging trajectories of personality change.