The cruise industry is estimated to be around US$45.6 billion with around 26 million passengers annually. The following is a list of the largest cruise lines with over 1,000 passengers annually and their market share by passengers and revenue as of 2018 according to Cruise Market Watch. The list also includes the combined market share of each of the cruise line holding companies: Carnival Corporation & plc, Royal Caribbean Cruises Ltd., Norwegian Cruise Line Holdings, and Genting Hong Kong.[6]