The registration tax will gradually be phased back in until 2020. These approaches are gradually being phased out. The existing series will be gradually phased out. The contract programs were gradually phased out. Subsidies were phased out to farmers and consumers. These operations have largely been phased out or significantly diminished. PBDEs have been largely phased out and replaced with alternative phosphate flame retardants. The target is gradually being phased in between 2012 and 2015. Older F-5 fighters are gradually being phased out but remain in service. Diesel services were introduced during the 1950s when steam was being phased out. Its use has been phased out in many newer aircraft. Outstanding TRuPS issues will be phased out completely by 2015. Domestic coal mining has been almost completely phased out. The 2007 edition has been gradually phased out. This scheme is being phased out in England, but remains in Wales and Northern Ireland.