▁and ▁dr illing ▁to ▁ref ining ▁and ▁market ing . ▁ ▁The ▁tax ▁also ▁appeared ▁to ▁be ▁a ▁complicated ▁tax ▁to ▁comp ly ▁with ▁and ▁to ▁admin ister . ▁ ▁A ▁ 1 9 8 4 ▁General ▁Account ing ▁Office ▁report ▁called ▁it ▁" per haps ▁the ▁largest ▁and ▁most ▁complex ▁tax ▁ever ▁lev ied ▁on ▁a ▁U . S . ▁industry ." ▁The ▁wind fall ▁profit ▁tax ▁was ▁im posed ▁on ▁oil ▁produ cers ▁when ▁tax able ▁cru de ▁oil ▁was ▁removed ▁from ▁the ▁oil - produ cing ▁property . ▁Any ▁individual ▁or ▁business ▁with ▁an ▁economic ▁interest ▁in ▁an ▁oil - produ cing ▁property ▁was ▁considered ▁as ▁a ▁producer ▁and ▁subject ▁to ▁the ▁tax . ▁There ▁were ▁four ▁kinds ▁of ▁produ cers ▁— ▁independent ▁produ cers , ▁integrated ▁oil ▁companies , ▁royal ty ▁own ers ▁( land own ers ), ▁and ▁tax - ex empt ▁parties . ▁There ▁were ▁about ▁one ▁million ▁oil ▁produ cers ▁( pers ons , ▁institutions , ▁and ▁business es ) ▁in ▁the ▁United ▁States ▁in ▁ 1 9 8 4 . ▁ ▁Sometimes ▁there ▁were ▁hundreds ▁of ▁people ▁having ▁a ▁fraction al ▁economic ▁interest ▁in ▁a ▁single ▁oil - produ cing ▁property . ▁ ▁Through out ▁the ▁comp liance ▁process , ▁many ▁tax ▁return ▁forms ▁and ▁information ▁forms ▁were ▁required . ▁The ▁process ▁was ▁further ▁complicated ▁due ▁to ▁numerous ▁exceptions ▁to ▁the ▁basic ▁general ▁rules ▁and ▁due ▁to ▁possible ▁interactions ▁between ▁the ▁wind fall ▁profit ▁tax ▁rules , ▁the ▁personal ▁and ▁corpor ate ▁income ▁tax ▁rules