In 1872, the Dole Gudbrandsdal was split into two types - a class for heavier agriculture and driving horses and a class for lighter racing and riding horses. In 1875, the Norwegian Trotting Association was formed by enthusiasts of the second type. In 1902, the first Dole Gudbrandsdal stud book was published, containing stallions from both types born between 1846 and 1892. In 1903, the Norwegian Trotting Association split their registration between purebred Norwegian trotters and trotting crosses. At the same time, standards for entry were tightened and the first inspection committee was created. In 1965, the Norwegian or Dole Trotter studbook was taken over by the Norwegian Trotting Association, as part of the new Coldblood trotter program approved by the Norwegian Ministry for Agriculture. The Dole Trotter studbook is still coordinated with the original Dole Gudbrandsdal registry, and horses have to meet many of the same standards. The Dole Trotter is alternately considered a subtype of the Dole Gudbrandsdal and a separate breed.