About 7 out of 10 establishments employ fewer than 10 workers, although more than 60 percent of all workers in this industry are employed in establishments with greater than 50 workers. As more large domestic oilfields and gasfields are depleted, major oil companies are focusing their exploration and production activity in foreign countries. Consequently, smaller companies with less capital for foreign exploration and production are drilling an increasing share of domestic oil and gas. Technology also has significantly decreased the risk and cost for smaller producers.

Relatively few oil and gas extraction workers are in their teens or early 20s. About 55 percent of the workers in this industry are between 35 and 54 years of age.