What is the frequency of leap in September?

The year of leap September is as follows:

Before and after 2 1 century, leap months were rare in September, and there were no leap months in the 20th, 24th, 25th and 27th centuries (but the frequency of leap months gradually increased with time). In the 200 years before 2020, 19 century is only 1832, 2 1 century is only 20 14 years, and 2200 will appear in 2 109 century.

Extended data

In the solar calendar, the earth revolves around the sun for a tropic year, with 365 days in a normal year and 366 days in a leap year. The traditional lunar calendar in China is based on the moon's profit and loss cycle, with a month of about 29.5306 days and a month of 12 of 354 days or 355 days, which is less than the solar calendar of 1 1 day.

The current lunar calendar method is "seven leaps in nineteen years". Every two to three years, 1 month must be added, and the added month is called leap month. Therefore, the lunar leap year has 13 months. Because of the leap in September, the Year of the Horse in Wu Jia has 384 days in the lunar calendar.

The leap month is set to coordinate the number of days between the solar calendar and the lunar calendar. The current method of setting leap years in the lunar calendar is "seventeen leap years in nineteen years", that is, seven leap years are added to the 19 lunar calendar. There are few leap months in September.

The last leap in September was at 1832, and the next leap will be at 2 109, which can be regarded as "once in a hundred years" and can only be met once in a lifetime.

Baidu encyclopedia-leap in September