MINNEAPOLIS  - Minnesota closed out 2015 with its highest level of boating fatalities in a decade.

Preliminary figures from the Department of Natural Resources show Minnesota had 18 boating-related deaths last year. That's the most since 23 people died in 2005.

Officials say it's an unhappy by-product of ideal spring, summer and fall weather that drew boaters out in droves.

Most of the deaths were the result of drownings. Of the 18 fatalities, 10 were men ages 20 to 60 years old who weren't wearing life jackets. The primary factor was victims falling overboard or boats capsizing.

October was the deadliest month, with five people killed while boating on Minnesota lakes.

While fatalities reached a 10-year high in 2015, the long-term trend is still downward in Minnesota.