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List of Leap Years

List of Leap Years

The standard calendar followed around the world is the Gregorian calendar. It has 12 months with 30 or 31 days out of which February is the only month that has 28 or 29 days. If there are 29 days in a year, it is called a 'leap year'. This Buzzle article provides a list of leap years from the year 1800 to 2400.
Batul Nafisa Baxamusa
Leap Year Babies
It is believed that people born on February 29 have unusual talents and personalities that reflect their special status. On the other hand, the Chinese believe that leap year babies are unlucky and difficult to raise.

The reformed Julian calendar, now known as Gregorian calendar, is followed all over the world today. It has two types of years, the common year and the leap year. The common years are years that have 365 days, but a leap year has an extra or intercalary day that adds one day to the year; thus having a total of 366 days.

This extra day is added to the year to synchronize the calendar year with the solar year. This means that it tries to match the length of time the earth requires to complete its orbit around the sun, that is, 365¼ days. The solar year is about 11 minutes less than 365¼ days in length. Therefore, to compensate the discrepancy, the extra day or leap year is omitted three times every four hundred years.

History of the Calendar

The first calendar was devised in 735 BCE by Romulus, the first Roman king. This calendar had 10 months instead of the usual 12 months. These 10 months were named as:
  • Martis, named after Mars, the Roman god of war
  • Aprilis, derived from the Latin word aperite, meaning 'to open', just as the flowers open during this month.
  • Maius, named after the mother of Mercury, Maia.
  • Junius, named after the queen of gods, Juno
The Latin numbers were used to derive the names from the fifth months onwards like:
  • Quintilis
  • Sextilis
  • September
  • October
  • November
  • December
As this calendar proved to be inaccurate compared to the solar year, King Numa added two extra months to the year and brought the number of days to 355 with Janaruis, named after Janus, the two-faced god and Febuarius, derived from Febura, a Roman feast. This calendar still had many problems and could not be rectified even by adding extra months. This confusion was cleared by another Roman emperor, Julius Caesar. He introduced the Julian calendar in 46 BCE. He tasked the best astronomers and geographers to correct the calendar. They calculated and concluded that the year should have 365¼ days. This could be made possible by following a cycle of three years with 365 days and followed by one leap year of 366 days. He added 30 and 31 days to consecutive months. Thus, March has 31 days, April 30 days, May 31 days, and so on. January, the month near to the winter solstice, was made the first month of the year. He added only 29 days in the month of February in a common year, and the intercalary day was inserted in February once every four years. Julius Caesar was honored by the Roman Senate by renaming Quinitis as 'Julius' (now July).

After the death of Julius Caesar, the priest made a mistake and started to add leap years every three years. It was corrected by Emperor Augustus in 8 BCE. Augustus too was honored by the Romans by renaming Sextilis as 'Augustus'. Emperor Augustus, was not happy with his month having fewer days than the month of Caesar. He therefore, added an extra day in his month making it 31 days. Thus, one day was subtracted from February, making it 28 days long in a common year, and 29 days long during the leap years. This Julian calendar was followed without any change for many centuries.

But, this calendar still had flaws. The average year was of 365.25 days long and the solar year length is 365.242216 days. This made the Julian calendar 11 minutes and 14 seconds longer. This little extra added up over the centuries, and led to the vernal equinox to fall on March 11, rather than March 21, during the 16th century. Thus, Pope Gregory XII moved the date by 11 days and made an exception to the rules of leap years. Now, according to the new rule, a century is a leap century only if it is divisible by 400. Thus, the average length of a Gregorian year is now 365.2425 days. The following table gives a list of leap years from the 1800s till the 2400s.

1801 - 2100
1804 1904 2004
1808 1908 2008
1812 1912 2012
1816 1916 2016
1820 1920 2020
1824 1924 2024
1828 1928 2028
1832 1932 2032
1836 1936 2036
1840 1940 2040
1844 1944 2044
1848 1948 2048
1852 1952 2052
1856 1956 2056
1860 1960 2060
1864 1964 2064
1868 1968 2068
1872 1972 2072
1876 1976 2076
1880 1980 2080
1884 1984 2084
1888 1988 2088
1892 1992 2092
1896 1996 2096
- 2000 -

2101 - 2400
2104 2204 2304
2108 2208 2308
2112 2212 2312
2116 2216 2316
2120 2220 2320
2124 2224 2324
2128 2228 2328
2132 2232 2332
2136 2236 2336
2140 2240 2340
2144 2244 2344
2148 2248 2348
2152 2252 2352
2156 2256 2356
2160 2260 2360
2164 2264 2364
2168 2268 2368
2172 2272 2372
2176 2276 2376
2180 2280 2380
2184 2284 2384
2188 2288 2388
2192 2292 2392
2196 2296 2396
- - 2400

The Gregorian calendar was adopted in 1752 in Great Britain. Thus, leap years are those that are divisible by 4 and leap centuries are those centuries that are divisible by 400. The chances of gaining one extra day will occur after around 3,300 years in the current Gregorian calendar. If you are wondering when is the next leap year, then according to the above list of leap years, 2016 will be the next leap year. You must have noticed the blank spaces and are wondering if the year 1900 was a leap year or not? Or even the coming years 2100, 2200, and 2300 will be leap years or not? Well, the answer is no! This is because they are divisible by 100 and not 400.
We hope you have understood what exactly a leap year is and the history behind it. Here's a short poem dedicated to leap years by an anonymous poet:
Thirty days hath September,
April, June and November.
All the rest have thirty-one,
Excepting February alone,
And that has twenty-eight days clear
And twenty-nine in each leap year.