There has been an important but unknown amount of unreported and otherwise secret production. We have discussed that relationship before and may again inside future.
OPEC Basket Price - For more detailed crude oil pricing, OPEC collects pricing data over a basket of seven crude oils, including: Algeria's Saharan Blend, Indonesia's Minas, Nigeria's Bonny Light, Saudi Arabia's Arab Light, Dubai's Fateh, Venezuela's Tia Juana Light, and Mexico's Isthmus (a non-OPEC crude oil).