Heightened sensitivity among men to the concerns of women over the past two decades is being cited by criminologists as a possible explanation for a dramatic decrease in rape attempts.

The rate of attempted rapes of girls and women in the United States decreased 46 percent from 1973 to 1987, according to a study released Sunday by the Justice Department.According to the Bureau of Justice Statistics study, the rate of attempted rapes fell from 1.3 per 1,000 girls and women in 1973 to 0.7 per 1,000 in 1987.

However, the rate of completed rapes - 0.6 per 1,000 - held steady over the same time span.

Criminologist Alfred Blumstein theorized that the decline in attempted rapes could be attributable to heightened male sensitivity to concerns raised by women in the last 20 years.

But Blumstein, dean of the school of urban and public affairs at Pittsburgh's Carnegie-Mellon University, said he could only guess at the reasons. Many women still are reluctant to report the crime, making statistics unreliable, he said.

Only 53 percent of rapes or attempted rapes are reported to police, the study said. But the report, compiled by extrapolating figures from a survey of 49,000 households, estimated there were 137,509 rapes and attempted rapes in 1987, down from 159,890 in 1973.

Women were more likely to call police if raped by a stranger than by someone they knew. Among women who were raped in or near their home, 48 percent said the attacker was someone they knew, according to the study, titled "Female Victims of Violent Crime."

Of the total violent crimes against women, rape accounted for 3 percent, the report said. The study found that 24.5 percent of the women who were victim of violent crimes - rape, robbery and assault - said they had been attacked by someone they knew intimately.