Common year starting on Thursday

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

A common year starting on Thursday is any non-leap year (i.e. a year with 365 days) that begins on Thursday, 1 January, and ends on Thursday, 31 December. Its dominical letter hence is D. The most recent year of such kind was 2015 and the next one will be 2026 in the Gregorian calendar[1] or, likewise, 2021 and 2027 in the obsolete Julian calendar, see below for more.

This is the only common year with three occurrences of Friday the 13th: those three in this common year occur in February, March, and November. Leap years starting on Sunday share this characteristic, for the months January, April and July. From February until March in this type of year is also the shortest period (one month) that runs between two instances of Friday the 13th.

Calendars

Applicable years

Gregorian Calendar

In the (currently used) Gregorian calendar, alongside Tuesday, the fourteen types of year (seven common, seven leap) repeat in a 400-year cycle (20871 weeks). Forty-four common years per cycle or exactly 11% start on a Thursday. The 28-year sub-cycle only spans across century years divisible by 400, e.g. 1600, 2000, and 2400.

Gregorian common years starting on Thursday[1]
Decade 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th
16th century prior to first adoption (proleptic) 1587 1598
17th century 1609 1615 1626 1637 1643 1654 1665 1671 1682 1693 1699
18th century 1705 1711 1722 1733 1739 1750 1761 1767 1778 1789 1795
19th century 1801 1807 1818 1829 1835 1846 1857 1863 1874 1885 1891
20th century 1903 1914 1925 1931 1942 1953 1959 1970 1981 1987 1998
21st century 2009 2015 2026 2037 2043 2054 2065 2071 2082 2093 2099
22nd century 2105 2111 2122 2133 2139 2150 2161 2167 2178 2189 2195
23rd century 2201 2207 2218 2229 2235 2246 2257 2263 2274 2285 2291
24th century 2303 2314 2325 2331 2342 2353 2359 2370 2381 2387 2398
25th century 2409 2415 2426 2437 2443 2454 2465 2471 2482 2493 2499
400-year cycle
0–99 9 15 26 37 43 54 65 71 82 93 99
100–199 105 111 122 133 139 150 161 167 178 189 195
200–299 201 207 218 229 235 246 257 263 274 285 291
300–399 303 314 325 331 342 353 359 370 381 387 398

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). A leap year has two adjoining dominical letters (one for January and February and the other for March to December, as 29 February has no letter). 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 3, 14 and 20 of the cycle are common years beginning on Thursday. 2017 is year 10 of the cycle. Approximately 10.71% of all years are common years beginning on Thursday.

Julian common years starting on Thursday
Decade 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th
15th century 1405 1411 1422 1433 1439 1450 1461 1467 1478 1489 1495
16th century 1506 1517 1523 1534 1545 1551 1562 1573 1579 1590
17th century 1601 1607 1618 1629 1635 1646 1657 1683 1674 1685 1691
18th century 1702 1713 1719 1730 1741 1747 1758 1769 1775 1786 1797
19th century 1803 1814 1825 1831 1842 1853 1859 1870 1881 1887 1898
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

Holidays

International

    • Valentine's Day falls on a Saturday
    • World Day for Grandparents and the Elderly falls on July 26
    • Halloween falls on a Saturday
    • Christmas Day falls on a Friday

Roman Catholic Solemnities

    • Epiphany falls on a Tuesday
    • Candlemas falls on a Monday
    • Saint Joseph's Day falls on a Thursday
    • The Annunciation of Jesus falls on a Wednesday
    • The Nativity of John the Baptist falls on a Wednesday
    • The Solemnity of Saints Peter and Paul falls on a Monday
    • The Transfiguration of Jesus falls on a Thursday
    • The Assumption of Mary falls on a Saturday
    • The Exaltation of the Holy Cross falls on a Monday
    • All Saints' Day falls on a Sunday
    • All Souls' Day falls on a Monday
    • The Feast of Christ the King falls on November 22 (or on its earliest possible date of October 25 in versions of the calendar between 1925 and 1962)
    • The First Sunday of Advent falls on November 29
    • The Immaculate Conception falls on a Tuesday
    • Gaudete Sunday falls on December 13
    • Rorate Sunday falls on December 20

Australia and New Zealand

    • Australia Day falls on a Monday
    • Waitangi Day falls on a Friday
    • Daylight saving ends on April 5
    • ANZAC Day falls on a Saturday
    • Mother's Day falls on May 10
    • Father's Day falls on September 6
    • Daylight saving begins on September 27 in New Zealand and October 4 in Australia

British Isles

    • Saint David's Day falls on a Sunday
    • Mother's Day falls on its earliest possible date of March 1, or on March 8, March 15, March 22 or March 29
    • Saint Patrick's Day falls on a Tuesday
    • Daylight saving begins on March 29
    • Saint George's Day falls on a Thursday
    • Father's Day falls on its latest possible date, June 21
    • Orangeman's Day falls on a Sunday
    • Daylight saving ends on its earliest possible date, October 25
    • Guy Fawkes Night falls on a Thursday
    • Saint Andrew's Day falls on a Monday

Canada

    • Daylight saving begins on its earliest possible date, March 8
    • Mother's Day falls on May 10
    • Victoria Day falls on its earliest possible date, May 18
    • Father's Day falls on its latest possible date, June 21
    • Canada Day falls on a Wednesday
    • Labour Day falls on its latest possible date, September 7 – this is the only common year when Victoria Day and Labour Day are sixteen weeks apart (they are fifteen weeks apart in all other common years)
    • Thanksgiving Day falls on October 12
    • Daylight saving ends on its earliest possible date, November 1

United States

    • Martin Luther King Jr. Day falls on January 19
    • President's Day falls on February 16
    • Daylight saving begins on its earliest possible date, March 8
    • Mother's Day falls on May 10
    • Memorial Day falls on its earliest possible date, May 25
    • Juneteenth falls on a Friday
    • Father's Day falls on its latest possible date, June 21
    • Independence Day falls on a Saturday
    • Labor Day falls on its latest possible date, September 7 – this is the only common year when Memorial Day and Labor Day are fifteen weeks apart (they are fourteen weeks apart in all other common years)
    • Grandparents' Day falls on its latest possible date, September 13
    • Columbus Day falls on October 12
    • Daylight saving ends on its earliest possible date, November 1
    • Thanksgiving Day falls on November 26

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. Retrieved 20 July 2017.