Via Statista (emphasis added):
"According to the Centers for Disease Control and Prevention (CDC), the prevalence of autism among U.S. children has risen significantly in recent years. While 6.7 in 1,000 children were diagnosed with autism spectrum disorder (ASD) in 2000, that number had risen to 27.6 in 1,000 children by 2020. This means that currently 1 in 36 children in the U.S. get diagnosed with ASD, up from 1 in 150 children 20 years ago.Acolytes of The Science™ will simply claim over and over that the reason there appears to be more autism at an ever-increasing clip is that doctors are just getting better at diagnosing it.
The reasons for this increase in prevalence are not fully understood and likely complex. Some possible factors that have been proposed include better awareness and screening for autism, changes in diagnostic criteria and environmental or genetic factors. Regardless of the reasons, this rise in the number of children with autism highlights the importance of early identification and intervention to help children with ASD reach their full potential."
The reason, for instance, they´ll claim, that autism is virtually non-existent in populations that pass on vaccines for kids and all other manner of modern pharmaceutical interventions, like the Amish, is that their autism simply isn't diagnosed properly.
Comment: See also: