Because of a natural human interest in misfortune, and because dramatic tales may lend legitimacy to a point of view, or product, or to an authoritarian personality,* it's possible to lose sight of how safe an activity backpacking actually is.
In 2002, visitors spent 1.9 million nights in the backcountry within the total U.S. National Park system. In 2003, there were 323 search and rescue missions associated with overnight hikers systemwide within the national parks.
There was a moderate resurgence of tourism in '03, but if the two years are roughly comparable, that means about one rescue per 11,000 nights out (30 years) or 0.00017 rescues per night.
Individuals might strive for a better-than-average safety performance, but of course, ought not assume they are immune to accidents and misfortune.
The 2003 NPS SAR totals are from an American Alpine Club report available on their Web site; the 2002 visitor number from an NPS Public Use Statistics site, which seems to lack comparable '03 visitor stats.
*As defined by Adorno, Sanford, et al.
