During 1971 the oil industry in North America drilled more than 27,000 mi of hole in 31,084 wells. Compared with 1970 this is a substantial decrease, approximately 7% in both wells and footage.

Each of the 3 countries had a decrease in drilling compared with 1970. The 27,300 wells in the United States represented a decrease of 7.4%, the 3,268 wells in Canada a slight decrease of 0.4%, and the 516 wells in Mexico a decrease of 1.3%.

Exploratory drilling on the North American continent continues to show a downward trend. The United States has been in a long-term downward trend since 1956. Canada has experienced declining exploratory activity since 1961. Mexico, however, has had about the same level of activity for the past 8 years.

New-field discoveries for the United States declined 12% compared with the previous year. These new fields found estimated reserves of 569 million bbl and 4.9 Tcf gas. Both reserve figures represent decreases compared with 1970; 28.7% for oil and 6.6% for gas.

If this downward trend in exploration drilling continues, the amount of future additions to domestic reserves from new-field discoveries must continue to decrease.