West Texas’ active Permian Basin added seven rigs actively drilling for oil this week.

While the Permian begins to boom, the net rig count in the rest of the country declined. The U.S. rig count grew by just four overall this week, including three drilling for oil and one seeking natural gas, according to Baker Hughes.

The Williston Basin, which is mostly in North Dakota, lost two rigs, while two rigs were removed from Colorado’s DJ-Niobrara basins. Louisiana lost four.

South Texas’ Eagle Ford shale, however, tacked on two.

The total count is 587 rigs, up from a low of 404 in May, according to Baker Hughes. Of the total, 477 are primarily drilling for oil.

The Permian now accounts for 235 rigs, almost half of the nation's oil rigs. The next most active area is Texas' Eagle Ford shale with 40 rigs, according to the Baker Hughes data.

Despite this week's increase, the oil rig count is down 70 percent from its peak of 1,609 in October 2014, before oil prices began plummeting. But U.S. oil prices have risen above $51 a barrel after OPEC agreed Wednesday to curb oil production.