There is a rookie classification system with a "Rookie of the Year" title for drivers who have not previously competed in this championship. The "Drivers' Trophy" was introduced in 2006 to provide a classification system and class title for drivers using chassis of between two and four years old. Eligibility for this "B class" was restricted to drivers who were not more than 22 years old at the start of the season. This class is no longer in use in 2007.