I apologize if this has already been posted, but NHTSA recently released a study on carseat and booster seat usage. The primary focus is on children 4 to 7 years of age but covers the whole span. It is based on a rigorous sampling methodology and includes comparisons against an earlier 2009 study.
http://www-nrd.nhtsa.dot.gov/Pubs/811718.pdf
Although there are still way too many children who ride completely unrestrained or (as the report calls it) "prematurely graduated" to the next stage, there is still a lot of good news in the report.
In particular, I noted that in the relatively short time from 2009 to 2011, the share of 1- to 3-years riding rear-facing more than doubled from 3% to 7%. Booster usage also increased and there were fewer kids inappropriately moved into seatbelt-only. We still have a long way to go.
http://www-nrd.nhtsa.dot.gov/Pubs/811718.pdf
Although there are still way too many children who ride completely unrestrained or (as the report calls it) "prematurely graduated" to the next stage, there is still a lot of good news in the report.
In particular, I noted that in the relatively short time from 2009 to 2011, the share of 1- to 3-years riding rear-facing more than doubled from 3% to 7%. Booster usage also increased and there were fewer kids inappropriately moved into seatbelt-only. We still have a long way to go.