In 2002, about six children aged eight years per every 1000 people in the general population received a diagnosis of autism spectrum disorder (ASD). The corresponding figure in 2008 was about 11 children, a 78% increase in just six years1.

To better understand how the increasing population of people with autism may impact adult programs, we examined the number of youth with autism served by state vocational rehabilitation programs in 2010. To account for the states' general population sizes, we reported the number of youth with autism served per 100,000 in the state general population (prevalence).

As Figure 1 shows, the prevalence of youth with autism who received vocational rehabilitation services varied substantially across states and ranged from 0.4 in Mississippi, Florida, South Carolina, and Nevada to a figure 14 times larger in Vermont (5.6). The white bars show seven states that reported at least one standard deviation2 smaller than average prevalence, whereas the blue bars show six states that reported at least one standard deviation greater than average prevalence. The red bars show average prevalence. Values falling one standard deviation either below or above average are worthy of attention, although they are not necessarily outliers. Outliers are defined as data points falling at least three standard deviation from the average. Only Vermont was an outlier because it reported a prevalence of youth served that was over three standard deviations above average.

Since eight-year-old children diagnosed with autism in 2008 will reach transition age in 2016, it is likely that state vocational rehabilitation programs will see substantial increases in the number of youth with autism seeking services in the coming years. Programs that have not yet experienced signs of this increase will likely do so in the next few years.