Editing Leap year starting on Saturday

{{Short description|none}}
A '''leap year starting on Saturday''' is any year with 366 days (i.e. it includes 29 February) that begins on [[Saturday]], 1 January, and ends on [[Sunday]], 31 December. Its [[dominical letter]]s hence are '''BA'''. The most recent year of such kind was [[2000]], and the next one will be [[2028]] in the [[Gregorian calendar]] or, likewise [[2012]] and [[2040]] in the obsolete [[Julian calendar]]. In the [[Gregorian calendar]], [[century leap year|years divisible by 400]] are always leap years starting on Saturday. The most recent such occurrence was [[2000]] and the next one will be [[2400]], see [[#Applicable years|below for more]].<ref name="math">{{cite web|url=https://webspace.science.uu.nl/~gent0113/calendar/isocalendar.htm |author=Robert van Gent |title=The Mathematics of the ISO 8601 Calendar |publisher=Utrecht University, Department of Mathematics |date=2017 |access-date=20 July 2017}} </ref>

Any leap year that starts on [[Saturday]] has only one [[Friday the 13th]]: the only one in this leap year [[October 13|occurs in October]]. [[common year starting on Sunday|Common years starting on Sunday]] share this characteristic, but also have another in [[January]]. From [[August]] of the [[Common year starting on Friday|common year preceding that year]] until [[October]] in this type of year is also the longest period (14 months) that occurs without a [[Friday the 13th]]. [[common year starting on Tuesday|Common years starting on Tuesday]] share this characteristic, from [[July]] of the year that precedes it to [[September]] in that type of year.

These types of years are the only ones which contain 54 different calendar weeks (2 partial, 52 in full) in areas of the world where Sunday is considered the first day of the week, and also the only type of year to contain 53 full weekends.

This year has four months (January, April, July and October) which begin on a weekend-day. This is also the only type of leap year in which the first and last day of the calendar year fall on weekend-days.

== Calendars ==
<!-- To avoid arbitrary years, use the most recent year of this type. 2000 was the most recent year of this type. -->
{{calendar|year=2000|show_year=off|title=Calendar for any [[leap year]] starting on Saturday,<br />presented as common in many English-speaking areas}}

{{calendar|year=2000|show_year=off|format=iso|row=3|zero=0|title=[[ISO 8601]]-conformant calendar with [[ISO week date|week numbers]] for<br />any leap year starting on Saturday (dominical letter BA)}}

== Applicable years ==
=== Gregorian Calendar ===
Leap years that begin on Saturday, along with those [[Leap year starting on Monday|starting on Monday]] and [[Leap year starting on Thursday|Thursday]], occur least frequently: 13 out of 97 (≈ 13.402%) total leap years in a 400-year cycle of the [[Gregorian calendar]]. Their overall occurrence is thus 3.25% (13 out of 400).

{| class="wikitable"
|+ Gregorian leap years starting on Saturday<ref name=math/>
!scope=row| Decade
! 1st !! 2nd !! 3rd !! 4th !! 5th !! 6th !! 7th !! 8th !! 9th !! 10th
|- style="opacity: 0.5;"

! style="background-color:#efefef;" | [[16th century]]
|colspan=9| ''prior to first adoption (proleptic)'' || [[1600]]
|-
! style="background-color:#efefef;" | [[17th century]]
|  ||  || [[1628]] ||  ||  || [[1656]] ||  ||  || [[1684]] || 
|-
! style="background-color:#efefef;" | [[18th century]]
|  ||  || [[1724]] ||  ||  || [[1752]] ||  || [[1780]] ||  || 
|-
! style="background-color:#efefef;" | [[19th century]]
|  || [[1820]]  ||  ||  || [[1848]] ||  ||  || [[1876]] ||  || 
|-
! style="background-color:#efefef;" | [[20th century]]
|  || [[1916]] ||  ||  || [[1944]] ||  ||  || [[1972]] ||  || [[2000]] 
|-
! style="background-color:#efefef;" | [[21st century]]
| ||  || [[2028]] ||  ||  || [[2056]] ||  ||  || [[2084 CE|2084]] || 
|-
! style="background-color:#efefef;" | [[22nd century]]
|  ||  || [[2124]] ||  ||  || [[2152]] ||  || [[2180]] ||  ||
|-
! style="background-color:#efefef;" | [[23rd century]]
|  ||  [[2220]] ||  ||  || [[2248]] ||  ||  || [[2276]] ||  || 
|-
! style="background-color:#efefef;" | [[24th century]]
|  || [[2316]] ||  ||  || [[2344]] ||  ||  || [[2372]] ||  || [[2400]] 
|-
! style="background-color:#efefef;" | [[25th century]]
| ||  ||  [[2428]] ||  ||  || [[2456]] ||  ||  || [[2484]] ||
|}

{| class="wikitable"
|+ 400-year cycle
|-
! 0–99
| 0 || 28 || 56 || 84
|-
! 100–199
| 124 || 152 || 180 ||
|-
! 200–299
| 220 || 248 || 276 ||
|-
! 300–399
| 316 || 344 || 372 ||
|}

{{List of calendars}}

=== Julian Calendar ===
Like all leap year types, the one starting with 1 January on a Saturday occurs exactly once in a [[solar cycle|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).

{| class="wikitable"
|+ Julian leap years starting on Saturday
!scope=row| Decade
! 1st !! 2nd !! 3rd !! 4th !! 5th !! 6th !! 7th !! 8th !! 9th !! 10th
|-
! style="background-color:#efefef;" | [[15th century]]
|  ||  || [[1424]] ||  ||  || [[1452]] ||  || [[1480]] ||  || 
|-
! style="background-color:#efefef;" | [[16th century]]
| [[1508]] ||  ||  || [[1536]] ||  ||  || [[1564]] ||  ||  || [[1592]]
|-
! style="background-color:#efefef;" | [[17th century]]
|  || [[1620]] ||  ||  || [[1648]] ||  ||  || [[1676]] ||  || 
|-
! style="background-color:#efefef;" | 18th century
| [[1704]] ||  ||  || [[1732]] ||  || [[1760]] ||  ||  || [[1788]] || 
|-
! style="background-color:#efefef;" | 19th century
|  || [[1816]] ||  ||  || [[1844]] ||  ||  || [[1872]] ||  || [[1900]]
|-
! style="background-color:#efefef;" | 20th century
|  ||  || 1928 ||  ||  || 1956 ||  ||  || 1984 || 
|-
! style="background-color:#efefef;" | 21st century
|  || 2012 ||  || 2040 ||  ||  || 2068 ||  ||  || 2096
|-
! style="background-color:#efefef;" | 22nd century
|  ||  || 2124 ||  ||  || 2152 ||  || 2180 ||  ||
|}

== Holidays ==

=== International ===
* [[Valentine's Day]] falls on a [[Monday]]
* The leap day ([[February 29]]) falls on a [[Tuesday]]
* [[Grandparents' Day|World Day for Grandparents and the Elderly]] falls on [[July 23]]
* [[Halloween]] falls on a [[Tuesday]]
* [[Christmas Day]] falls on a [[Monday]]

=== Roman Catholic Solemnities ===
* [[Epiphany (holiday)|Epiphany]] falls on a [[Thursday]]
* [[Candlemas]] falls on a [[Wednesday]]
* [[Saint Joseph's Day]] falls on a [[Sunday]]
* The [[Annunciation of Jesus]] falls on a [[Saturday]]
* The [[Nativity of John the Baptist]] falls on a [[Saturday]]
* The [[Solemnity of Saints Peter and Paul]] falls on a [[Thursday]]
* The [[Transfiguration of Jesus]] falls on a [[Sunday]]
* The [[Assumption of Mary]] falls on a [[Tuesday]]
* The [[Exaltation of the Holy Cross]] falls on a [[Thursday]]
* [[All Saints' Day]] falls on a [[Wednesday]]
* [[All Souls' Day]] falls on a [[Thursday]]
* The [[Feast of Christ the King]] falls on its latest possible date, [[November 26]] (or on [[October 29]] in versions of the calendar between 1925 and 1962)
* The [[First Sunday of Advent]] falls on its latest possible date, [[December 3]]
* The [[Immaculate Conception]] falls on a [[Friday]]
* [[Gaudete Sunday]] falls on its latest possible date, [[December 17]]
* [[Rorate Sunday]] falls on its latest possible date, [[December 24]]

=== Australia and New Zealand ===
* [[Australia Day]] falls on a [[Wednesday]]
* [[Waitangi Day]] falls on a [[Sunday]]
* [[Daylight saving]] ends on [[April 2]]
* [[ANZAC Day]] falls on a [[Tuesday]]
* [[Mother's Day]] falls on its latest possible date, [[May 14]]
* [[Father's Day]] falls on [[September 3]]
* Daylight saving begins on its earliest possible date, [[September 24]] in New Zealand and [[October 1]] in Australia

=== British Isles ===
* [[Saint David's Day]] falls on a [[Wednesday]]
* [[Mother's Day]] falls on [[March 5]], [[March 12]], [[March 19]], [[March 26]] or [[April 2]]
* [[Daylight saving]] begins on [[March 26]]
* [[Saint Patrick's Day]] falls on a [[Friday]]
* [[Saint George's Day]] falls on a [[Sunday]]
* [[Father's Day]] falls on [[June 18]]
* [[Orangeman's Day]] falls on a [[Wednesday]]
* Daylight saving ends on [[October 29]]
* [[Guy Fawkes Night]] falls on a [[Sunday]]
* [[Saint Andrew's Day]] falls on a [[Thursday]]

=== Canada ===
* [[Daylight saving]] begins on [[March 12]]
* [[Mother's Day]] falls on its latest possible date, [[May 14]]
* [[Victoria Day]] falls on [[May 22]]
* [[Father's Day]] falls on [[June 18]]
* [[Canada Day]] falls on a [[Saturday]]
* [[Labour Day (Canada)|Labour Day]] falls on [[September 4]]
* [[Thanksgiving Day (Canada)|Thanksgiving Day]] falls on [[October 9]]
* Daylight saving ends on [[November 5]]

=== United States ===
* [[Martin Luther King Jr. Day]] falls on [[January 17]]
* [[President's Day]] falls on its latest possible date, [[February 21]]
* [[Daylight saving]] begins on [[March 12]]
* [[Mother's Day]] falls on its latest possible date, [[May 14]]
* [[Memorial Day]] falls on [[May 29]]
* [[Father's Day]] falls on [[June 18]]
* [[Juneteenth]] falls on a [[Monday]]
* [[Independence Day (United States)|Independence Day]] falls on a [[Tuesday]]
* [[Labor Day (United States)|Labor Day]] falls on [[September 4]]
* [[Grandparents' Day]] falls on [[September 10]]
* [[Columbus Day]] falls on [[October 9]]
* Daylight saving ends on [[November 5]]
* [[Election Day (United States)|Election Day]] falls on [[November 7]]
* [[Thanksgiving Day]] falls on [[November 23]]

==References==
{{Commons category}}
{{reflist}}
{{List of calendars}}

{{DEFAULTSORT:Leap Year Starting On Saturday}}
[[Category:Gregorian calendar]]
[[Category:Julian calendar]]
[[Category:Saturday]]