229.Assessment has indicated that the likely safety benefits from the Rail Accident Investigation Branch can be expected to cover the expected costs. RAIB will have an estimated base case cost over the period 2003-2012 of £17m. This will be borne by the existing budget of the Department for Transport, in the same manner as is done with the Air and Marine Accident Investigation Branches (AAIB & MAIB). A 21/2% reduction in numbers of accidents over 2003-2012 would yield a £22m benefit in the base case.