The International Association for Healthcare Security and Safety(IAHSS) Foundation has just released the results from its 2016 Healthcare Crime Survey. Overall, the rate of violent crime reported by the study’s 326 U.S. participants dropped dramatically from 2.8 incidents per 100 hospital beds in 2014 to .09 incidents per 100 beds last year, representing a 68 percent decrease.

The reasons for the significant decrease are not clear, however, according to report author Karim H. Vellani, who is president of Threat Analysis Group LLC, “Others have speculated that the growing concern regarding workplace violence over the past several years resulted in security improvements, which finally paid off in 2015. Wish we knew definitively.”

Unlike the violent crime rate, which went down, the assault rate edged up slightly in 2015 compared to the previous year, from 7.8 assaults per 100 beds to 8.1 assaults per 100 beds. That being said, the rate last year was less than in 2013, which recorded 11.1 assaults per 100 beds.

Most of the aggravated assaults and assaults were type 2: Violence directed at employees by customers, clients, patients, students, inmates or any others to whom the employer provides a service.

Disorderly conduct was up about 14 percent in 2015 (21.4 compared to 18.8 in 2014) but still much less than in 2013 when the rate was 39.2 incidents per 100 beds.

Burglary and theft rates also decreased last year (by 20 percent for burglary and about 19 percent for theft), while the rate of motor vehicle thefts remained the same at .3 incidents per 100 beds. The rate of vandalism decreased by 16 percent in 2015 compared to 2014.