That 100% of children under 5 years of age require a child restraint
90% of 6 to 8 year olds require a booster seat as does
50% of 9 to 10 year olds and
10% of children aged 10 to 12 years.
These children still need to use some form of child restraint, this is most likely a booster seat for older children and a harnessed car seat for younger children. This does not mean that children out grow their car seat the day they turn 5. Remember your child is 5 years old until the day of their 6th birthday.