This figure shows the notification rate of syphilis of more than two years or unknown duration in Australia in 2011, by age group and sex. The figure shows that the rate of infection was higher in males than in females in all age groups, except among those aged 10 to 14 and 15 to 19 years. The figure also demonstrates the bimodal distribution of the notification rates, with the first peak occurring among males aged 40 to 44, and females aged 35 to 39, and the second peak occurring among males aged over 85 and females aged 80 to 84 years.