Domestic oil and gas drilling finished 1999 on a strong note, two separate reports indicate. But one of them suggests that drilling could experience a moderate seasonal decline during the next few months. Estimated completions of U.S. oil and gas wells and dry holes increased 4.9% year-to-year to 5,442, from 5,188 during fourth-quarter 1998, according to the American Petroleum Institute's latest quarterly well-completion report. Natural gas provided the impetus for the increase as the number of gas wells drilled climbed 17.7% to 3,363, from 2,857 in 1998's final three months. During that same period, oil well drilling declined by 3.3% to 1,236 from 1,278 wells, while the number of dry holes dropped 19.9% to 843 from 1,053. Total estimated exploratory completions declined 10.8% year-to-year, to 481 from 539, while development completions rose 6.7% to 4,961 from 4,649 in the comparable 1998 period. API also reported a 31.8% decrease in total footage drilled during 1999's fourth quarter to 19,551,000 feet from 28,685,000 feet a year earlier. Meanwhile, Salomon Smith Barney Inc. reported a 31.2% increase in its adjusted total of U.S. drilling permits, to 2,445 in December 1999 from 1,864 a year earlier. On a month-to-month basis, the latest total represented a 21.8% decline from November 1999's level of 3,125, the peak level for the year. "The recent sequential and year-over-year changes suggest a moderate seasonal decrease in drilling activity in the coming months," said Mark S. Urness, who follows drilling contractors for Salomon Smith Barney in New York. His survey indicates that a large part of the decrease during December occurred in Texas, where the total number of drilling permits, on a gross basis, dropped 39.1% to 602 from 989 in November. December's figure also represented a 40.9% plunge from September's 1,018 drilling permits, a six-year peak for the Lone Star State. But it also came in 55.6% higher than the May 1999 total of 387, which represented a six-year low for Texas, according to Salomon Smith Barney's figures. -Nick Snow