Self-esteem increases in early and middle childhood, remains constant in adolescence, increases strongly in young adulthood, continues to increase in middle adulthood, peaks between 60 & 70, & then declines in old age, with a sharper drop in very old age

Orth, U., Erol, R. Y., & Luciano, E. C. (2018). Development of self-esteem from age 4 to 94 years: A meta-analysis of longitudinal studies. Psychological Bulletin. Advance online publication. http://dx.doi.org/10.1037/bul0000161

Abstract: To investigate the normative trajectory of self-esteem across the life span, this meta-analysis synthesizes the available longitudinal data on mean-level change in self-esteem. The analyses were based on 331 independent samples, including data from 164,868 participants. As effect size measure, we used the standardized mean change d per year. The mean age associated with the effect sizes ranged from 4 to 94 years. Results showed that average levels of self-esteem increased from age 4 to 11 years (cumulative d = 0.34; cumulative ds are relative to age 4), remained stable from age 11 to 15, increased strongly until age 30 (cumulative d = 1.05), continued to increase until age 60 (cumulative d = 1.30), peaked at age 60 and remained constant until age 70, declined slightly until age 90 (cumulative d = 1.15), and declined more strongly until age 94 (cumulative d = 0.76). Moderator analyses were conducted for the full set of samples and for the subset of samples between ages 10 to 20 years. Although the measure of self-esteem accounted for differences in effect sizes, the moderator analyses suggested that the pattern of mean-level change held across gender, country, ethnicity, sample type, and birth cohort. The meta-analytic findings clarify previously unresolved issues about the nature and magnitude of self-esteem change in specific developmental periods (i.e., childhood, adolescence, and old age) and draw a much more precise picture of the life span trajectory of self-esteem.