NEW YORK — Even as the election outcome intensifies the US abortion debate, a comprehensive new survey finds the annual number of abortions in the nation has dropped to well under 1 million, the lowest level since 1974.

The report, which counted 926,200 abortions in 2014, was released Tuesday by the Guttmacher Institute, a research group that supports abortion rights. It is the only entity which strives to count all abortions in the United States; the latest federal survey by the Centers for Disease Control and Prevention lacks data from California, Maryland and New Hampshire.

The total from 2014 represented a drop of 12.5 percent from Guttmacher’s previous survey, which tallied 1.06 million abortions in 2011. The decrease was spread nationwide; in only six states did abortions increase over the three-year span.

According to the report, the abortion rate was 14.6 abortions per 1,000 women aged 15-44, the lowest rate since abortion was legalized nationally in 1973 by the Supreme Court’s Roe v. Wade decision.

Following that ruling, the number of abortions in the country rose steadily — reaching a peak of 1.6 million in 1990 — before starting a decline.

The authors of the new report, Guttmacher researchers Rachel Jones and Jenna Jerman, said the latest phase of the decline was likely the result of two main factors: the increased availability of affordable, long-lasting contraceptives that have reduced unintended pregnancies, and the surge of abortion restrictions in many states that have forced some clinics to close.

Associated Press