A total of 46,609 people required search and rescue aid in the country’s national parks between 2004 and 2014.
The death toll from those incidents was 1,578, while another 13,957 people were injured or fell ill, data from the National Park Service show. Search and rescue costs topped $51.4 million during that span.
The National Park Service tracks detailed statistics on search and rescue missions within its 84 million acres of parks.
In 2014 alone, the most recent year for which data was provided, a total of 3,409 people required search and rescue assistance in a total of 2,658 incidents.
In that same year, the parks recorded more than 292 million visits.
That means that for every 100,000 visits, 1 person needed search and rescue aid.
In 2014, 164 fatalities were reported from search and rescue cases, while 1,184 people were injured or fell ill. More than $4 million was spent on those missions.
Earlier this week, the Globe reported that search and rescue missions are frequent in New Hampshire, a heavily-forested state that features dozens of mountains and popular hiking routes.
Data tracked by that state’s Fish and Game Department show that someone needs to be rescued by that agency from the New Hampshire wilderness every two-and-a-half days, on average, and that the fall and winter seasons can be particularly busy and dangerous.
The National Park Service’s detailed national statistics for 2014 provide other insights about search and rescue missions:
• Men accounted for nearly 53 percent of people needing search and rescue aid.
• People between ages 20 and 29 accounted for the largest share, about 17 percent, of people needing help.
• The most common places for search and rescue missions were mountains between 5,000 and 15,000 feet, which accounted for about one in five cases, followed by mountains and foothills below 5,000 feet, which accounted for another 15 percent of incidents. Missions in canyons were the next most common.
• The most common activity that search and rescue subjects were doing at the time was daytime hiking, which accounted for 42 percent of cases. Following that was overnight hiking, 13 percent; non-motorized boating, 10 percent; motorized boating, 7.5 percent; and swimming, at 6 percent.
• The most common factors that contributed to the people who needed help were: fatigue/physical condition, 22.8 percent; people being insufficiently informed or making an error in judgment, 18.8 percent; falls, 10 percent; insufficient equipment, clothing, or experience, 8 percent; and darkness, 6 percent.
• Subjects of searches were found within 24 hours in the vast majority of cases, about 93 percent. In a small number of cases, about 3 percent of search missions, the worst-case outcome happened: The subjects of the hunt were never found.