A preliminary estimate of the total crude oil production from Texas, the No. 1 oil producer in the nation, shows output remains resilient, state data show.

The Railroad Commission of Texas, the state's energy regulator, reports a preliminary estimate of crude oil production in August, the last full month for which data are available, was about 2.41 million barrels per day. That's an increase of nearly 8 percent year-on-year.

Crude oil prices started falling steadily in mid-2014 when markets moved toward the supply side because of the glut of oil coming from U.S. shale basins and weak global economic growth. China's economy, once growing at a double-digit pace, is slowing down and other major economies, like the United States and Europe, are growing, but at an anemic pace.

Low crude oil prices have left energy companies with less money to invest in exploration and production, though data show few signs that weak economics have caught up with output figures.

Later reports from Texas, however, may show crude oil production declines. The U.S. Energy Information Administration said in its latest monthly market report total U.S. crude oil production declined by 120,000 barrels per day from August to September. By next year, EIA expects crude oil production to fall from the expected 2015 average of 9.2 million bpd to 8.9 million bpd.

Low spending on exploration and production, meanwhile, means fewer rigs deployed across many inland shale basins in the United States. Baker Hughes in a weekly market snapshot reported Texas lost five rigs for the week ending Oct. 23.

EIA finds drilling activity, already at historic lows, should be limited as long as West Texas Intermediate, the U.S. benchmark price for crude oil, stays below $60 per barrel. WTI traded early Tuesday at $43.67 per barrel.