Chinese New Year day or even one moon cycle due to using a meridian based on a different capital city in a different time zone or different placements of intercalary months. Chinese calendar defines the lunar month with winter solstice as the 11th month, which means that Chinese New Year usually falls on the second new moon after the winter solstice (rarely the third if an intercalary month intervenes). In more than 96% of the years, the Chinese New Year's Day is the closest new moon to lichun () on 4 or 5 February, and the first new moon after Dahan (). In
Leap year lunar months containing 29 or 30 days, generally in alternating order. However, the tabular Islamic calendar used by Islamic astronomers during the Middle Ages and still used by some Muslims does have a regular leap day added to the last month of the lunar year in 11 years of a 30-year cycle. This additional day is found at the end of the last month, Dhu 'l-Hijja, which is also the month of the Hajj. The Hijri-Shamsi calendar, also adopted by the Ahmadiyya Muslim Community, is based on solar calculations and is similar to the Gregorian calendar in its structure with