From an Old Tractor website

[Southpaw]

If using some common sense it is safer for your butt on a tractor seat than probably in a car driving down the highway. However if splitting hairs it is older men on old tractors where more accidents occur. I guess old fools and their toys.

Still remember watching my 80 year old gran-daddy bush hog a pasture on the side of steep hill on the old family farm in central Kentucky using his old tractor. Portions of that hill hit 45 degrees. He never rolled a tractor but he came close. He was ornery. Still remember my exasperated grand mother giving him what for about mowing that hill. For the record though that hill had been a pasture for probably over 100 years so it was doable but you had to know your stuff and it was not for the faint of heart.

I guess knowing what your doing on an old tractor is the same with shooting old guns if done right.

Here is some non tractor specific info.

Abstract

Farm tractors have historically been identified as the leading source of work-related farming deaths in the U.S. While data from the National Safety Council show that tractor-related deaths and fatality rates have decreased since 1969, current surveillance data indicate that an average of 218 farmers and farmworkers die annually from tractor-related injuries. Of these deaths, approximately 120 are associated with tractor overturns. Most of these deaths occur to tractor operators 65 years of age and older. Roll-over Protective Structures (ROPS) have been identified as the single best method of preventing tractor overturn-related deaths, yet only 38% of all tractors used on farms in the U.S. were equipped with ROPS in 1993. A major issue associated with increasing the use of ROPS on farm tractors is the cost of retrofitting ROPS on older tractors. The average cost to retrofit tractors with ROPS in the U.S. was estimated at $937, and a cost of at least $4 billion nationally in 1993.

Doing the math that means there are about 4.2 million death traps out there.