Since I began in my field of developmental pediatrics over 30 years ago, we certainly have more children being diagnosed with autism or spectrum disorders today. In fact, 30 years ago there was no such condition as autistic spectrum disorders. So one of the factors that has contributed is the increased diagnostic criteria that includes many children who would never have been diagnosed autistic in the past. California, who has been keeping track of developmental disabilities and is, I believe, the only state in the country that does so, has shown a significant increase over that period of time. But it is also true that there has been a decrease in the incidents of mental retardation diagnoses during the same period of time. And so there does seem to be some shifting, in my opinion, from children who previously may have been diagnosed with mental retardation who are now being diagnosed with autistic spectrum disorders. Whether there's actually a real increase in autism and autism spectrum disorders over the last 30 years is difficult to tell because of the differences in diagnostic criteria over the last 30 years. It's a bit like comparing apples and oranges, and it's hard to get a firm grip whether we actually are seeing the increase that some people on the internet would claim.