This is the 52nd consecutive annual report on drilling activity for the United States. Canadian drilling data have been included with these annual reports since 1948; Mexico provided data for the period 1948-1980.

For 1987, Canada showed an 18.1% increase in total wells drilled (7,078 wells) and a 14.9% increase in the amount of footage drilled (28,369,980 ft). The 64 new-field wildcat discoveries represented a success rate of 30.7%. Of these discoveries, 35 were in Alberta, 13 were in Saskatchewan, and 14 were in British Columbia. New-field and new-pool wildcats accounted for 34.9% of the 1,318 exploratory discoveries. In Canada, 55.6% of the 2,369 exploratory wells drilled were successful.

In the United States, total drilling activity during 1987 decreased 29.6% (to 35,917 wells), and footage drilled decreased 26.9% (to 30,448 mi) compared with 1986. There were 506 new-field discoveries--a 26.9% decrease from 1986. The ratio of new-field dry holes to producers was 6.34:1, and the success rate was 13.6%.

Estimates of ultimate reserves reported as discovered in 1983-1987 in the United States are being reviewed by the Joint Task Group on Statistical Integrity of the Committee on Statistics of Drilling. Results of this study will be published in a later issue of the Bulletin.