A leap year starting on Friday is any year with 366 days (i.e. it includes 29 February) that begins on Friday 1 January and ends on Saturday 31 December. Its dominical letters hence are CB. The most recent year of such kind was 2016, and the next one will be 2044 in the Gregorian calendar, and 2000 and 2028 in the obsolete Julian calendar.

Any leap year that starts on Friday has only one Friday the 13th. The only one in this leap year occurs in May. Common years starting on Saturday share this characteristic.

Calendars

Applicable years Gregorian Calendar Leap years that begin on Friday, along with those starting on Sunday, occur most frequently: 15 of the 97 (≈ 15.46%) total leap years in a 400-year cycle of the Gregorian calendar. Thus, their overall occurrence is 3.75% (15 out of 400).

For this kind of year, the ISO week 10 (which begins March 7) and all subsequent ISO weeks occur later than in all other leap years. + Gregorian leap years starting on Friday Decade 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 16th century prior to first adoption (proleptic) 158817th century161616441672 18th century 1712 1740 1768 1796 19th century 1808 1836 1864 1892 20th century 1904 1932 1960 1988 21st century 2016 2044 2072 22nd century 2112 2140 2168 2196 23rd century 2208 2236 2264 2292 24th century 2304 2332 2360 2388 25th century 2416 2444 2472 26th century 2512 2540 2568 2596

+ 400-year cycle 0–99 16 44 72 100–199 112 140 168 196 200–299 208 236 264 292 300–399 304 332 360 388

Julian Calendar Like all leap year types, the one starting with 1 January on a Friday occurs exactly once in a 28-year cycle in the Julian calendar, i.e. in 3.57% of years. As the Julian calendar repeats after 28 years that means it will also repeat after 700 years, i.e. 25 cycles. The year's position in the cycle is given by the formula ((year + 8) mod 28) + 1).

+ Julian leap years starting on Friday Decade 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 15th century 1412 1440 1468 1496 16th century 1524 1552 1580 17th century 1608 1636 1664 1692 18th century 1720 1748 1776 19th century 1804 1832 1860 1888 20th century 1916 1944 1972 2000 21st century 2028 2056 2084 22nd century 2112 2140 2168 2196

Holidays

International Valentine's Day falls on a Sunday. This is the only type of leap year when Valentine’s Day falls in ISO week 6. They fall in ISO week 7 in all other leap years. The leap day (February 29) falls on a Monday. World Day for Grandparents and the Elderly falls on July 24. Halloween falls on a Monday. Christmas Day falls on a Sunday. This is the only type of leap year when Christmas Day falls in ISO week 51. They fall in ISO week 52 in all other leap years.

Roman Catholic Solemnities Epiphany falls on a Wednesday Candlemas falls on a Tuesday Saint Joseph's Day falls on a Saturday The Annunciation of Jesus falls on a Friday The Nativity of John the Baptist falls on a Friday The Solemnity of Saints Peter and Paul falls on a Wednesday The Transfiguration of Jesus falls on a Saturday The Assumption of Mary falls on a Monday The Exaltation of the Holy Cross falls on a Wednesday All Saints' Day falls on a Tuesday All Souls' Day falls on a Wednesday The Feast of Christ the King falls on its earliest possible date, November 20 (or on October 30 in versions of the calendar between 1925 and 1962) The First Sunday of Advent falls on its earliest possible date, November 27. This is the only leap year when The First Sunday of Advent falls in ISO week 47. They fall in ISO week 48 in all other leap years. The Immaculate Conception falls on a Thursday Gaudete Sunday falls on its earliest possible date, December 11. This is the only leap year when Gaduete Sunday falls in ISO week 49. They fall in ISO week 50 in all other leap years. Rorate Sunday falls on its earliest possible date, December 18. This is the only leap year when Rorate Sunday falls in ISO week 50. They fall in ISO week 51 in all other leap years.

Australia and New Zealand Australia Day falls on a Tuesday Waitangi Day falls on a Saturday Daylight saving ends on April 3 ANZAC Day falls on a Monday Mother's Day falls on its earliest possible date, May 8. This is the only leap year when Mother’s Day falls in ISO week 18. They fall in ISO week 19 in all other leap years. Father's Day falls on September 4 Daylight saving begins on September 25 in New Zealand and October 2 in Australia

British Isles Saint David's Day falls on a Tuesday Mother's Day falls on March 6, March 13, March 20, March 27 or April 3 Daylight saving begins on March 27 Saint Patrick's Day falls on a Thursday Saint George's Day falls on a Saturday Father's Day falls on June 19 Orangeman's Day falls on a Tuesday Daylight saving ends on October 30 Guy Fawkes Night falls on a Saturday Saint Andrew's Day falls on a Wednesday

Canada Daylight saving begins on March 13 Mother's Day falls on its earliest possible date, May 8. This is the only leap year when Mother’s Day falls in ISO week 18. They fall in ISO week 19 in all other leap years Victoria Day falls on May 23 Father's Day falls on June 19 Canada Day falls on a Friday Labour Day falls on September 5 Thanksgiving Day falls on October 10 Daylight saving ends on November 6

United States Martin Luther King Jr. Day falls on January 18 President's Day falls on its earliest possible date, February 15. This is the only leap year when President’s Day falls in ISO week 7. They fall in ISO week 8 in all other leap years. This is also the only leap year when Labor Day that precedes this type of year to President’s Day in this type of year are only 23 weeks apart. They are 24 weeks apart in all other leap years. Daylight saving begins on March 13 Mother's Day falls on its earliest possible date, May 8. This is the only leap year when Mother’s Day falls in ISO week 18. They fall in ISO week 19 in all other leap years. Memorial Day falls on May 30 Juneteenth and Father's Day coincide on Sunday, June 19. This is the only leap year when Juneteenth falls in ISO week 24. They fall in ISO week 25 in all other leap years. Independence Day falls on a Monday Labor Day falls on September 5 Grandparents' Day falls on September 11 Columbus Day falls on October 10 Daylight saving ends on November 6 Election Day falls on its latest possible date, November 8 Thanksgiving Day falls on November 24

References