A person's high school grade point average may be a strong predictor of their future earnings, according to a recent study.

Researchers from the University of Miami found that a one-point increase in high school GPA raises annual earnings in adulthood by around 12 percent for men and 14 percent for women. Although previous studies have found a relationship between higher levels of education and greater earnings, less is known about the association between academic performance in high school and income.

"Conventional wisdom is that academic performance in high school is important for college admission, but this is the first study to clearly demonstrate the link between high school GPA and labor market earnings many years later," Michael T. French, lead researcher of the study and director of the Health Economics Research Group (HERG) in the Department of Sociology at the UM College of Arts and Sciences, said in a statement.

For the study, researchers used multiple waves of data from the National Longitudinal Survey of Adolescent Health. The information included high school records, demographic and background information from more than 10,000 males and females. Educational attainment and income information was obtained when the respondents were between 24 and 34 years of age, approximately ten years after high school graduation.

Based on the findings, overall high school GPA is significantly higher among women, but men have significantly higher annual earnings. For this reason, the researchers analyzed men and women separately. Even so, the study finds that a one-point increase in GPA doubles the probability of completing college-from 21 percent to 42 percent-for both genders.

Researchers said the findings can have important implications for policymakers, teachers and school administrators who wish to promote academic achievement for students.

"High school guidance counselors and teachers can use these findings to highlight the importance of doing well in high school for both short term (college admission) and longer term (earnings as an adult) goals," French said.

The findings were recently published in the Eastern Economic Journal.