The number of wells producing crude oil and natural gas in the United States declined 4.6% to 991,000 in 2017, from a peak of 1.039 million in 2014, according to the U.S. Energy Information Administration. The decline is a result of advances in technology and drilling techniques.
The number of vertical wells has fallen 8.1% to 864,000 in 2017, from 940,000 in 2014. Over the same period, the number of horizontal wells that were drilled rose 28.3% to 127,000, from 99,000. The number of horizontal wells drilled in 2017 accounted for 13% of total wells drilled, up from 10% in 2014.
Horizontal wells are more expensive to drill than vertical wells, but horizontal wells contact more reservoir rock and produce greater volumes. In 2017, 1% of vertical wells produced at least 100 barrels of crude oil per day, but 30% of horizontal wells produced at least 100 barrels per day. Crude oil production has continued to rise as the number of wells has fallen.
U.S. production rose 6.9% to 9.3 million barrels per day in 2017, from 8.7 million barrels per day in 2014. Over the same period, gross withdrawals of natural gas in the United States increased 6% to 83.4 billion cubic feet per day, from 78.7 billion cubic feet per day. Crude oil and natural gas production have continued to increase, and in August, the production levels reached 11.3 million barrels per day and 85.2 billion cubic feet per day, respectively.
The majority of U.S. oil and natural gas production comes from wells producing between 50 barrels of oil equivalent per day and 1,600 barrels of oil equivalent per day, according to the EIA. Wells within this range accounted for 9% of the total number of wells but 62% of crude oil production and 63% of natural gas production.