Stability and change in the Big Five personality domains: evidence from a longitudinal study of Australians

Longitudinal data from a nationally representative sample of Australians were used to evaluate mean-level differences and rank-order stability in personality traits assessed twice over a 4-year time span (n = 13,134). Extraversion, Neuroticism, and Openness declined over the life span, whereas Agreeableness increased among young cohorts, was stable among middle-aged cohorts, and declined among the oldest old. Cross-sectional analyses suggested an increase in Conscientiousness throughout the life span, though longitudinal analyses suggested a slight decline in late life. There was an inverted U-shaped pattern for rank-order stability, with peak stability occurring in middle age. For three of the Big Five domains (Extraversion, Agreeableness, and Conscientiousness), age-related differences appeared to be somewhat more pronounced before age 30 than after age 30.