Following World War 2,the money available to invest in yachting had dwindled due to wartime losses,It was too expensive to keep building the large 23-meter puls boats. There were no races held between 1938 and 1957.So,when the America's Cup returned in 1958,the Twelve-Meter Class rule was implemented,making the boats smaller,lighter and faster. For the next 31 years, the Twelve-Meter rule was the standard.