ENERGY

Increase in Oil and Gas Rig Activity Reported: The number of rigs exploring for oil and gas in the United States made a healthy gain for the second week in a row, climbing by 35 to 755 last week, Houston’s Baker Hughes Inc. reported. The number peaked at 4,500 in December, 1981, during the oil boom and dropped to a record low of 596 this summer. Ike Kerridge, a vice president at Baker Hughes, believes that the increase in the last two weeks was primarily because of speculation that a federal tax credit for drilling in geologic formations may not be renewed after it expires Dec. 31. He also pointed to recent increases in the price of natural gas.