seat belt and helmet use estimates and breaks them out by the six major categories
recorded in the Moving Traffic Study: seating position, vehicle type, region, time of week, time of day, and
ambient enforcement law. This table also gives the overall estimates of use of legal and illegal helmets. The
2001-2002 changes that are significant with 95% confidence are identified and conversion rates given in
order to highlight categories that appear to have undergone substantial shifts in use.