English: Bar chart of the number (per 1,000 U.S. resident children aged 6–17) of children aged 6–17 who were served under the Individuals with Disabilities Education Act (IDEA) with a diagnosis of autism, from 1996 through 2007. Counts of children diagnosed with autism for each year were taken from Table 1-9 of IDEA Part B Child Count (2005) and from Table 1-11 of IDEA Part B Child Count (2007). These were divided by census estimates for U.S. resident population aged 6–17 taken from US census estimates for 1990–1999 resident population by age and the similar estimates for 2000–2007; for all years, the September population estimates were used.