 Hurricane histories for individual states had been constructed by the 1990s as well, which proposed new storms and increased the knowledge of tropical cyclones already in the database.Due to this profusion of relevant information not included in HURDAT, and evolving definitions for tropical and subtropical cyclones over the decades, the project was started around 2000 to update the official database.Since then, the International Comprehensive Ocean-Atmosphere Data Set has been utilized to check for older ship reports which were either not utilized nor available to previous researchers.