The number of U.S. oil-drilling rigs, viewed as a proxy for activity in the sector, has fallen sharply since oil prices began to fall. But it hasn’t fallen enough to relieve the global glut of crude. There are now about 72% fewer rigs of all kinds from a peak of 1,609 in October 2014. According to Baker Hughes, the number of U.S. gas rigs rose by one to 89 from a week ago . The U.S. offshore-rig count was 25 in the latest week, down one from the previous week and down eight from a year earlier. Oil prices rose Friday , continuing their strong week, amid signs that the energy glut may be waning and the global economy may be improving. Recently, U.S. crude oil gained 6% to $39.52 a barrel.