table of contents notes to consolidated financial statements of american airlines group inc . purposes that permitted approximately $ 9.0 billion ( with $ 6.6 billion of unlimited nol still remaining at december 31 , 2015 ) of the federal nols carried over from prior taxable years ( nol carryforwards ) to be utilized without regard to the annual limitation generally imposed by section 382 . see note 10 for additional information related to tax matters