Direct link to the CDC report :

Prevalence of Autism Spectrum Disorder Among Children Aged 8 Years — Autism and Developmental Disabilities Monitoring Network, 11 Sites, United States, 2010 Surveillance Summaries March 28, 2014 / 63(SS02);1-21

http://www.cdc.gov/mmwr/preview/mmwrhtml/ss6302a1.htm?s_cid=...