The number of abortion providers in the United States continues to dwindle, and Bloomberg reported Wednesday that the rate of their disappearance is at its highest point on record.

The procedure is legal across the country, though Republican lawmakers in several states have passed a variety of laws in recent years that make it more difficult for clinics to operate.

Citing data from the Guttmacher Institute, a non-profit with a focus on reproductive health, Bloomberg reported the United States lost more than 150 standalone clinics between the late 1980s and 2011. The number stood at 553 in 2011 and has declined further in subsequent years.

Bloomberg conducted its own analysis and found 162 abortion providers stopped performing the procedure — or closed entirely — in the past five years, a little more than one every two weeks.

Bloomberg reported that 35 states lost at least one provider since 2011, and restrictive laws were to blame for more than 40 of the closings. At least 30 closures occurred in Texas, whose abortion regulations are the subject of a lawsuit that will be reviewed by the Supreme Court on March 2.

Other providers closed because of business decisions, reduced demand or a lack of doctors, Bloomberg found, and only 21 new clinics have opened since 2011 amid the rising challenges.