The number of rigs drilling for oil in the U.S. climbed one in the past week to 407, resuming a rise after a string of recent increases was snapped last week, according to oil-field services company Baker Hughes Inc. BHI -0.10 % The U.S. oil-rig count is typically viewed as a proxy for activity in the sector. After peaking at 1,609 in October 2014, low oil prices put downward pressure on production and the rig count fell sharply. The oil-rig count had risen for eight weeks in a row before last week. The nation’s gas-rig count rose by seven in the past week, to 88. The U.S. offshore-rig count fell by seven rigs from last week to 10, which is 23 fewer than a year ago. On Friday, oil prices were up 3% but still on track for one of the biggest weekly drops since January .