In most U.S. states, moving violations, including running red lights and speeding, assess points on a driver's driving record. Since more points indicate an increased risk of future violations, insurance companies periodically review drivers' records, and may raise premiums accordingly. Rating practices, such as debit for a poor driving history, are not dictated by law. Many insurers allow one moving violation every three to five years before increasing premiums. Accidents affect insurance premiums similarly. Depending on the severity of the accident and the number of points assessed, rates can increase by as much as twenty to thirty percent. Any motoring convictions should be disclosed to insurers, as the driver is assessed by risk from prior experiences while driving on the road.
Two of the most important factors that go into determining the underwriting risk on motorized vehicles are: performance capability and retail cost. The most commonly available providers of auto insurance have underwriting restrictions against vehicles that are either designed to be capable of higher speeds and performance levels, or vehicles that retail above a certain dollar amount. Vehicles that are commonly considered luxury automobiles usually carry more expensive physical damage premiums because they are more expensive to replace. Vehicles that can be classified as high performance autos will carry higher premiums generally because there is greater opportunity for risky driving behavior. Motorcycle insurance may carry lower property-damage premiums because the risk of damage to other vehicles is minimal, yet have higher liability or personal-injury premiums, because motorcycle riders face different physical risks while on the road. Risk classification on automobiles also takes into account the statistical analysis of reported theft, accidents, and mechanical malfunction on every given year, make, and model of auto.