Among many calendar reform proposals that eliminate the constant seven-day week in exchange for simplified calculation of calendrical data like weekday names for given dates, some retain Sabbatical influences. The Hermetic Lunar Week Calendar uses moon phases, resulting in weeks of six to nine days. The International Fixed Calendar and World Calendar both consist of 364-day years containing exactly 52 weeks (each starting on a day designated as Sunday), with an additional one or two intercalary "blank" days not designated as part of any week (Year Day and Leap Day in the International Fixed Calendar; Worldsday and Leapyear Day in the World Calendar). Reform supporters sought to accommodate Sabbatical observance by retaining the modified week and designating the intercalary days as additional Sabbaths or holidays; however, religious leaders held that such days disrupt the traditional seven-day weekly cycle. This unresolved issue contributed to the cessation of reform activities in the 1930s (International Fixed Calendar) and again in 1955 (World Calendar), though supporters of both proposals remain.