The following graph shows a noticeable increase in offender rates after the age of 12 years. A person aged 13 years had more than twice the offending rate than 12 year olds. The increase in offender rates continued until the offender rates peaked in the later teenage years; for combined states and territories this was at 17 years of age (6,968 offenders per 100,000 persons aged 17 years). The peak offender rate ranged between 16 to 18 years across the different states and territories.
Youth offender rate (a),
Age by combined selected states and territories (b)