Common year starting on Friday

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Short description: Type of year C on a solar calendar according to its starting and ending days in the week


A common year starting on Friday is any non-leap year (i.e. a year with 365 days) that begins on Friday, 1 January, and ends on Friday, 31 December. Its dominical letter hence is C. The most recent year of such kind was 2021 and the next one will be 2027 in the Gregorian calendar,[1] or, likewise, 2011, 2022 and 2033 in the obsolete Julian calendar, see below for more. This common year is one of the three possible common years in which a century year can begin on, and occurs in century years that yield a remainder of 100 when divided by 400. The most recent such year was 1700 and the next one will be 2100.

Any common year that starts on Wednesday, Friday or Saturday has only one Friday the 13th: the only one in this common year occurs in August. Leap years starting on Thursday share this characteristic, but also have another one in February.

From July of the year that precedes this year until September in this type of year is the longest period (14 months) that occurs without a Friday the 17th. Leap years starting on Tuesday share this characteristic, from August of the common year that precedes it to October in that type of year.

Calendars

This is the only year type where the nth "Doomsday" (this year Sunday) is not in ISO week n; it is in ISO week n-1.

Applicable years

Gregorian calendar

In the (currently used) Gregorian calendar, alongside Sunday, Monday, Wednesday or Saturday, the fourteen types of year (seven common, seven leap) repeat in a 400-year cycle (20871 weeks). Forty-three common years per cycle or exactly 10.75% start on a Friday. The 28-year sub-cycle only spans across century years divisible by 400, e.g. 1600, 2000, and 2400.

Gregorian common years starting on Friday[1]
Decade 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th
16th century prior to first adoption (proleptic) 1593 1599
17th century 1610 — 1621 1627 1638 1649 1655 1666 1677 1683 1694 1700
18th century 1706 1717 1723 1734 1745 1751 1762 1773 1779 1790 —
19th century 1802 1813 1819 1830 — 1841 1847 1858 1869 1875 1886 1897
20th century 1909 1915 1926 1937 1943 1954 1965 1971 1982 1993 1999
21st century 2010 — 2021 2027 2038 2049 2055 2066 2077 2083 2094 2100
22nd century 2106 2117 2123 2134 2145 2151 2162 2173 2179 2190 —
23rd century 2202 2213 2219 2230 — 2241 2247 2258 2269 2275 2286 2297
24th century 2309 2315 2326 2337 2343 2354 2365 2371 2382 2393 2399
400-year cycle
0–99 10 21 27 38 49 55 66 77 83 94
100–199 100 106 117 123 134 145 151 162 173 179 190
200–299 202 213 219 230 241 247 258 269 275 286 297
300–399 309 315 326 337 343 354 365 371 382 393 399

Julian calendar

In the now-obsolete Julian calendar, the fourteen types of year (seven common, seven leap) repeat in a 28-year cycle (1461 weeks). This sequence occurs exactly once within a cycle, and every common letter thrice.

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). Years 4, 15 and 26 of the cycle are common years beginning on Friday. 2017 is year 10 of the cycle. Approximately 10.71% of all years are common years beginning on Friday.

Julian common years starting on Friday
Decade 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th
15th century 1406 1417 1423 1434 1445 1451 1462 1473 1479 1490 —
16th century 1501 1507 1518 1529 1535 1546 1557 1563 1574 1585 1591
17th century 1602 1613 1619 1630 — 1641 1647 1658 1669 1675 1686 1697
18th century 1703 1714 1725 1731 1742 1753 1759 1770 — 1781 1787 1798
19th century 1809 1815 1826 1837 1843 1854 1865 1871 1882 1893 1899
20th century 1910 — 1921 1927 1938 1949 1955 1966 1977 1983 1994
21st century 2005 2011 2022 2033 2039 2050 — 2061 2067 2078 2089 2095

Holidays

International

    • Valentine's Day falls on a Sunday
    • World Day for Grandparents and the Elderly falls on July 25
    • Halloween falls on a Sunday
    • Christmas Day falls on a Saturday

Roman Catholic Solemnities

    • Epiphany falls on a Wednesday
    • Candlemas falls on a Tuesday
    • Saint Joseph's Day falls on a Friday
    • The Annunciation of Jesus falls on a Thursday
    • The Nativity of John the Baptist falls on a Thursday
    • The Solemnity of Saints Peter and Paul falls on a Tuesday
    • The Transfiguration of Jesus falls on a Friday
    • The Assumption of Mary falls on a Sunday
    • The Exaltation of the Holy Cross falls on a Tuesday
    • All Saints' Day falls on a Monday
    • All Souls' Day falls on a Tuesday
    • The Feast of Christ the King falls on November 21 (or on its latest possible date of October 31 in versions of the calendar between 1925 and 1962)
    • The First Sunday of Advent falls on November 28
    • The Immaculate Conception falls on a Wednesday
    • Gaudete Sunday falls on December 12
    • Rorate Sunday falls on December 19

Australia and New Zealand

    • Australia Day falls on a Tuesday
    • Waitangi Day falls on a Saturday
    • Daylight saving ends on April 4
    • ANZAC Day falls on a Sunday, and in some years coincides with Easter Sunday falling on its latest possible date
    • Mother's Day falls on May 9
    • Father's Day falls on September 5
    • Daylight saving begins on September 26 in New Zealand and October 3 in Australia

British Isles

    • Saint David's Day falls on a Monday
    • Mother's Day falls on March 7, March 14, March 21, March 28 or on its latest possible date of April 4
    • Daylight saving begins on March 28
    • Saint Patrick's Day falls on a Wednesday
    • Saint George's Day falls on a Friday, and in some years coincides with Good Friday falling on its latest possible date
    • Father's Day falls on June 20
    • Orangeman's Day falls on a Monday
    • Daylight saving ends on its latest possible date, October 31
    • Guy Fawkes Night falls on a Friday
    • Saint Andrew's Day falls on a Tuesday

Canada

    • Daylight saving begins on its latest possible date, March 14
    • Mother's Day falls on May 9
    • Victoria Day falls on its latest possible date, May 24
    • Father's Day falls on June 20
    • Canada Day falls on a Thursday
    • Labour Day falls on September 6
    • Thanksgiving Day falls on October 11
    • Daylight saving ends on its latest possible date, November 7

United States

    • Martin Luther King Jr. Day falls on January 18
    • President's Day falls on its earliest possible date, February 15
    • Daylight saving begins on its latest possible date, March 14
    • Mother's Day falls on May 9
    • Memorial Day falls on its latest possible date, May 31
    • Juneteenth falls on a Saturday
    • Father's Day falls on June 20
    • Independence Day falls on a Sunday
    • Labor Day falls on September 6
    • Grandparents' Day falls on September 12
    • Columbus Day falls on October 11
    • Daylight saving ends on its latest possible date, November 7
    • Thanksgiving Day falls on November 25

References

  1. ↑ 1.0 1.1 Robert van Gent (2017). "The Mathematics of the ISO 8601 Calendar". Utrecht University, Department of Mathematics. https://webspace.science.uu.nl/~gent0113/calendar/isocalendar.htm. 



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