By DAVID CRARY, AP National Writer

NEW YORK (AP) — Even as the election outcome intensifies America's abortion debate, a comprehensive new survey finds the annual number of abortions in the U.S 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 which supports abortion rights. It is the only entity which strives to count all abortions in the U.S.; 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 U.S. 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 and hindered many women's access to the procedure.

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Guttmacher's state-by-state breakdown showed big declines in abortions in some liberal states, such as California, that protect abortion rights, and also in some conservative states, such as Texas, that have passed laws to restrict abortions.

Jones noted that the majority of women who get abortions have low incomes, and nearly two-thirds are already parents.

"It can be very difficult for them to arrange for time off from work, transportation and child care," Jones said. "Some of the abortion rate decline is likely attributable to women who were prevented from accessing needed services."

The highest abortion rates were in the District of Columbia, New York, New Jersey, Maryland and Florida. The lowest rates were in Wyoming, Mississippi and South Dakota, states that had only one abortion clinic operating in 2014.

According to the report, the number of abortion clinics nationwide declined by 6 percent — from 839 in 2011 to 788 in 2014.

The report's release comes 10 days before the anti-abortion movement's annual March for Life in Washington, D.C., and at a time when the movement is emboldened by the outcome of the recent presidential, congressional and state elections.

In Congress, majority Republicans in both chambers are seeking to halt federal funding for Planned Parenthood, which provided more than one-third of the nation's abortions in 2014, and also to ban most abortions after 20 weeks of pregnancy. President-elect Donald Trump has promised to sign both measures if they reach his desk, and also says he wants to fill a vacancy on the Supreme Court with a "pro-life" justice.

One of Trump's top advisers, Kellyanne Conway, is scheduled to speak at the March for Life.

At the state level, tough new restrictions on abortion are being pushed in numerous Republican-controlled state legislatures, including Iowa and Kentucky, where the recent election gave the GOP full control. In Kentucky, lawmakers have already moved swiftly to enact a ban on abortions after 20 weeks and to require doctors to perform ultrasounds prior to abortions.

In some cases, abortion-rights supporters are fighting back with legal challenges, such as an effort by the American Civil Liberties Union to block Kentucky's new ultrasound bill.

Abortion-rights leaders also are warning that progress in reducing unintended pregnancies could be derailed by efforts to defund Planned Parenthood, a major supplier of contraceptives, and to repeal the Affordable Care Act, which greatly expanded health-insurance coverage of contraceptives.