sentences:  According to the 2014 report from GAMA (General Aviation Manufacturers Association), there are 362,000 general aviation aircraft worldwide, and 199,000 (or roughly 55%) are based in the United States.No single insurer has the resources to retain a risk the size of a major airline, or even a substantial proportion of such a risk.The catastrophic nature of aviation insurance can be measured in the number of losses that have cost insurers hundreds of millions of dollars (Aviation accidents and incidents).