Determination of the day of the week in the year row (07) is located in column G. The letter in the century row (13) and column G is E, so the day of the week is Friday. January 1 corresponds to G, G in the year row (00) corresponds to F in the century row (20), and F corresponds to Saturday. A pithy formula for the method: ""Date letter (G), letter (G) is in year row (00) for the letter (F) in century row (20), and for the day, the letter (F) become weekday (Saturday)"". Use 17 (in the Gregorian century row, column C) and 83 (in
Week 7, 8, 9 and 10 days, of which the weeks of 4, 8 and 9 days are interrupted to fit into the 210-day cycle. A 10-day week, called "décade", was used in France for nine and a half years from October 1793 to April 1802; furthermore, the Paris Commune adopted the Revolutionary Calendar for 18 days in 1871. The Bahá'í calendar features a 19-day period which some classify as a month and others classify as a week. The International Fixed Calendar (also known as the "Eastman plan") fixed every date always on the same weekday. This plan kept a 7-day