Denning points out the shift in Mexico to becoming a net oil importer from the U.S. by August 2013, that put new urgency to the passage of the oil law in Mexico for attracting foreign investment. Mexico's exports of crude oil were about 0.9 million barrels a day in August 2013. U.S. refinery products imported by Mexico including gasoline on an oil equivalent basis were 0.8 million barrels a day. Mexico became a net importer of energy in March 2013. Another negative factor in the energy trade between Mexico and the U.S. is increasing U.S. oil production and refineries in the coast of the Gulf of Mexico being full. As this U.S. production increases Mexico would have to offer competitive discounts in the future. Pemex drillled in all 25 deepwater wells in the last decade, according to Sanford Bernstein. The U.S. in the same period drilled 1500 ultra-deep water wells alone, showing the urgent need for foreign investment in the Mexican oil industry.