Similar numbers and rates of reporting, founding, and charging for the three levels of assault and manslaughter were also analyzed as a basis for comparison. Between 1983 and 1988, there was a steady increase in the number of sexual assaults reported to the police. There was also an increase in the number of sexual assault crisis centers and special units within police forces to handle sexual assault cases. Most sexual assault reports to the police in 1988 were classified as Level I, the least serious category. The proportion of reports considered to be unfounded did not change substantially after 1983. There was a significant decline in the unfounded rate of aggravated sexual assault, from 20 percent in 1983 to 8 percent in 1989. Of all founded sexual assault reports, 49 percent were cleared by charging. At the national level, there was a systematic trend for sexual assault offense clearance rates to rise in relation to crime seriousness. It was determined that Canadian legislation dealing with sexual assault had minimal impact on sexual assault reporting.