According to the World Health Organization (WHO), Body Mass Index (BMI) is a statistic that indicates the ratio of a person's weight to their body volume. The Center for Disease Control (CDC) uses the table to classify children from ages 2 to 20. Because BMI values change as children grow, the CDC uses percentiles rather than fixed values for BMI. Percentiles provide a basis of comparison for BMI over time. Weight status Percentile range
Underweight: Less than the 5th percentil
Healthy weight: 5th percentile to less than the 85th percentile
Overweight: 85th to less than the 95th percentile
Obese: Equal to or greater than the 95th percentile

Based on data from WHO, a representative sample of 15-year-old males could consist of the following 15 values.

18.1, 18.6, 15.9, 17.6, 21.9, 16.9, 20.8, 19.4, 21.3,
22.7, 19.0, 20.3, 19.8, 30.8, 24.3

85th percentile: