Table 1: Professor Gray’s seven hurricane summary statistics.

NSNamed StormsNumber of storms with winds exceeding 35 knots
NSDNamed Storm DaysNumber of storm days with winds exceeding 35 knots
HHurricanesNumber of storms with winds exceeding 64 knots
HDHurricane DaysNumber of storm days with winds exceeding 64 knots
IHIntense HurricanesNumber of storms with winds exceeding 96 knots
IHDIntense Hurricane DaysNumber of storm days with winds exceeding 96 knots
NTCNet Tropical Cyclone ActivityA relative measure of a given year’s tropical cyclone activity.