Preliminary state data show crude oil production in Texas is on the rise, though drilling permits for February are down 45 percent year-on-year.

The Railroad Commission of Texas, the state energy regulator, reported total crude oil production for January, the last full month for which data are available, was 2.2 million barrels per day, a 15 percent increase over January 2014.

Texas is the No. 1 oil producer in the nation. About half of all rigs actively exploring for or producing oil in the United States are in Texas.

In February, the commission issued 827 new permits for oil and gas wells. The total number of drilling permits, however, was down 45 percent from February 2014.

The low price of oil is forcing energy companies to spend less on exploration and production, the upstream side of the energy sector, and to cut back on staff. Many U.S. energy companies have headquarters in Houston.

In January, the Federal Reserve Bank of Dallas said it was less optimistic about its outlook for the year because of the low price of oil. In its so-called Beige Book, the bank said demand for oil services in the Permian and Eagle Ford shale basins declined. Oil services company Halliburton announced cuts in staff from its Houston offices the same week.

In its latest report on manufacturing, the Dallas bank said it expected "fairly weak" business conditions in the state.