WASHINGTON (AP) -- The number of people who were victims of all violent crimes except murder fell by 9 percent in 2001, sending the crime rate to its lowest level since it was first tracked in 1973, the government reported Sunday.

The decline was due primarily to a record low number of reported assaults, the most common form of violent crime.

The drop is detailed in the 2001 National Crime Victimization Survey, which is based on interviews with victims and thus does not include murder.

The Bureau of Justice Statistics report was obtained Sunday by The Associated Press in advance of its release this week.

Preliminary figures from another FBI report -- gleaned from more than 17,000 city, county and state law enforcement agencies and released in June -- reflected an increase in murders of 3.1 percent in 2001.

Experts discussing the new report on violent crime said the decrease, part of a decade-long trend, is the result primarily of the strong economy in the 1990s and the prevalence of tougher sentencing laws.

"Despite our perceptions, based on television or chats around the water-cooler, it is clear crime is on the decline in a significant way and has been for some years now," said Ralph Myers, a criminologist at Stanford University.

"When people have jobs and poor neighborhoods improve, crime goes down," Myers said. "Crime also has been impacted by the implementation of tough sentencing laws at the end of the 1980s."

Since 1993, the violent crime rate has decreased by almost 50 percent.

The new report says that between 2000 and 2001, the number of people who reported they were victims of violent crime fell from about 28 per 1,000 to about 25 per 1,000, a 10 percent drop. The number of people reporting violent crimes fell from 6,323,000 in 2000 to 5,744,000 in 2001.