National Highway Traffic Safety Administration National Highway Traffic Safety Administration National Highway Traffic Safety Administration National Highway Traffic Safety Administration National Highway Traffic Safety Administration NHTSA identifies Department of National Transportation estimates National Highway Traffic Safety Administration National Highway Traffic Safety Administration National Highway Traffic Safety Administration Drowsy Driving and Automobile Crashes National Highway Traffic Safety Administration National Highway Traffic Safety Administration National Highway Traffic Safety Administration NHTSA NHTSA National Highway Traffic Safety Administration Drowsy Driving and Automobile Crashes National Highway Traffic Safety Administration National Highway Transportation Safety Administration National Highway Traffic Safety Administration National Highway Traffic Safety Administration DROWSY DRIVING National Highway Traffic Safety Administration National Highway Traffic Safety Administration National Highway Traffic Safety Administration National Highway Traffic Safety Administration chance NHTSA National Highway Traffic Safety Administration National Highway Traffic Safety Administration a study Drowsy Driving Florida.org National Highway Traffic Safety Administration Drowsy Driving and Automobile Crashes $12.4 billion per year. car accident National Highway Traffic Safety Administration National Department of Transportation estimates National Highway Transportation Safety Administration National Highway Traffic Safety Administration