Pemex, the public company in charge of exploration, extraction, transportation and marketing of crude oil and natural gas, as well as the refining and distribution of petroleum products and petrochemicals, is one of the largest companies in the world by revenue, making US$86 billion in sales a year. Mexico is the sixth-largest oil producer in the world, with 3.7 million barrels per day. In 1980 oil exports accounted for 61.6% of total exports; by 2000 it was only 7.3%.