Line chart showing the number of annual avalanche related fatalities in Colorado from 1955 to 2023, as of May 2, 2023. In 1955, there were none. There were less than 10 annually between 1955 and 1986. It jumped to 11 in 1987, but dropped again consistently. In 2023, there were 11. While years varied, the five-year average rose from one in 1955 to nine in 2023.