The WRC was formerly held for Group A and Group B rallycars. However, due to the increasing power, lack of reliability and a series of fatal accidents during the 1986 rally, Group B was permanently banned. Later, in 1997, the Group A cars evolved into the WRC car spec, to ease the development of new cars and bring new makes to the competition. In 2011, new rules were introduced to encourage more manufacturers (and privateers) to take part, because the recent economic downturn had prompted several manufacturers to leave the championship.