For the fourth consecutive year, the number of index offenses in Illinois has declined. Total index offenses declined to 606,566 in 1998, compared to 666,492 in 1994. Much of this decline was due to a decline in the number of violent offenses. Property offenses also declined, but not as dramatically as violent offenses. The number of violent offenses declined 20.4 percent, compared with a 17.6-percent decline nationally. Murders declined by 27 percent. Criminal sexual assaults fell 19 percent; and aggravated assaults, the most frequently reported violent offense, declined 14.8 percent. The number of property offenses declined by 6.3 percent. Robberies had the greatest decrease among index crimes, decreasing just under 30 percent. The number of burglaries declined 14.9 percent. Although Illinois' population continues to increase (5.2 percent between 1990 and 1998), the violent offense rate declined from 1,063 offenses for every 100,000 persons in 1994 to 828 offenses for every 100,000 persons in 1998. 2 figures and 2 tables