(Screen Capture/PBS)

(CNSNews.com) - In 40 straight Gallup polls over a span of 24 years, a majority of Americans have said that they believe abortion should be illegal in all or most circumstances.

In the latest Gallup survey examining the issue, which was conducted May 1-10, 53 percent said they believe abortion should be illegal in all or most circumstances.

The Gallup survey asks this question: “Do you think abortion should be legal under any circumstances, legal only under certain circumstances, or illegal in all circumstances?”

If the respondent says they believe abortion should be “legal only under certain circumstances,” Gallup asks this follow-up question: “Do you think abortion should be legal in most circumstances or only in a few circumstances?"

Since September 1994, Gallup has asked these questions in 40 polls. In every one of those 40 polls, the combined percentage of people who said they believe abortion should be illegal in “all circumstances” or legal “only in a few circumstances” has exceeded 50 percent.

The percentage who said that abortion should be illegal in all or most circumstances hit a high of 63 percent in the poll that Gallup conducted on Aug. 12-13, 1997. In that survey, 22 percent said they thought abortion should be legal under any circumstances, 12 percent said it should be legal under most circumstances, 48 percent said it should be legal only in a few circumstances and 15 percent said it should be illegal in all circumstances.

Thus, in that survey, 63 percent (48 percent plus 15 percent) said abortion should be illegal in all but a few or all cases.

The lowest percentage of respondents who have told Gallup they believe abortion should be illegal in most or all circumstances was 51 percent—the percentages who took that position in surveys conducted Sept. 6-7, 1994 and Sept. 22-24, 1995.

Since 1995, the percentage has never dropped that low again.

In the latest survey in which Gallup asked the question, which was conducted May 1-10 of this year, 29 percent said they thought abortion should be legal under any circumstances, 14 percent said they thought it should be legal under most circumstances, 35 percent said they thought it should be legal only in a few circumstances, and 18 percent said they thought it should be illegal in all circumstances.

In the 40 polls in which Gallup has asked this question over the last 24 years, 57.58 percent of Americans on average have said they believe abortion should be illegal in all or all but a few cases.