section_path: Calculations/The four gates/Incidence
section_name: Incidence
paragraph_text: Incidence
  
  Comparing the days of the week of molad Tishrei with those in the kevi'ah shows that during 39% of years 1 Tishrei is not postponed beyond the day of the week of its molad Tishrei, 47% are postponed one day, and 14% are postponed two days. This table also identifies the seven types of common years and seven types of leap years. Most are represented in any 19-year cycle, except one or two may be in neighboring cycles. The most likely type of year is 5R7 in 18.1% of years, whereas the least likely is 5C1 in 3.3% of years. The day of the week of 15 Nisan is later than that of 1 Tishrei by one, two or three days for common years and three, four or five days for leap years in deficient, regular or complete years, respectively.