Introduction

Technological innovation in drilling and production has caused rapid growth in U.S. oil and natural gas production during the past few years. One way of developing deeper insight into this rapid growth is to probe how U.S. oil and natural gas wells have changed. This report looks at the distribution of wells by size and technology to understand these trends.

U.S. oil production reached 9.97 million barrels per day (b/d) in December 2017 and 12.04 million b/d in December 2018, and U.S. natural gas gross withdrawals reached 97.59 billion cubic feet per day (Bcf/d) in December 2017 and 108.56 Bcf/d in December 2018[1]. At the same time, the number of producing wells in the United States increased from 729,000 in 2000 to a high of 1,035,000 wells in 2014, then declined to 982,000 wells in 2018—mostly because of lower oil prices (Figure 1). Technological change is reflected in the increase in the share of horizontal wells during the past decade from 3% to 14% (2008–2018) (Figure 2). Most U.S. oil and natural gas production comes from wells that produce between 100 barrels of oil equivalent per day (BOE/d) and 3,200 BOE/d (Figures 3 and 4, respectively). Interestingly, the share of U.S. oil and natural gas wells producing less than 15 BOE/d has remained surprisingly steady at about 80% from 2000 through 2018 (Figure 1).

This report provides yearly estimates of the number of producing oil and natural gas wells in the United States, which are grouped according to volume in one of 22 production volume brackets that range from less than 1 BOE/day to more than 12,800 BOE/day. EIA designates wells as either oil or natural gas wells based on a gas-oil ratio (GOR) of 6,000 cubic feet (cf) of natural gas to 1 barrel (b) of oil (cf/b) for each year’s production. If the GOR is equal to or less than 6,000 cf/b, then we classify the well as an oil well. If the GOR is greater than 6,000 cf/b, we classify the well as a natural gas well.

This report includes four sections:

An explanation of what a well is
Methodology
Frequently asked questions
Suggestions for querying the downloadable Excel data file of state-level data

The distribution tables for the production rates of all U.S. oil and natural gas wells include the years 2000 through 2018. Appendix B provides summary breakouts for the total United States, each state, the Federal Gulf of Mexico, and the Federal Pacific. The Appendix C spreadsheet can be used to generate figures for all regions and for additional variables.

The quality and completeness of the available data we used to build the tables varies by state. The data originate from state administrative records of monthly well- or lease-level natural gas and liquid production. EIA receives the data from the commercial source Enverus Drillinginfo, which collects the data from the various state agencies. Some state agencies do not make well-production data available until years after production occurs, and others have never made well-production data available. For the late-reporting states—Arizona, Kentucky, Maryland, and Tennessee—we use the last year of reported data to populate recent missing years to achieve the most complete U.S. total well counts. Data are not available for Illinois and Indiana.