A leap year starting on Monday is any year with 366 days (i.e. it includes 29 February) that begins on Monday, 1 January, and ends on Tuesday, 31 December. Its dominical lettershence are GF. The most recent year of such kind was 1996 and the next one will be 2024 in the Gregorian calendar[1] or, likewise, 2008, and 2036 in the obsolete Julian calendar. Any leap year that starts on Monday, Wednesday or Thursday has two Friday the 13ths. This leap year contains two Friday the 13ths in September and December. Common years starting on Tuesday share this characteristic. In this leap year, the leap day, U.S. Independence Day, and Halloween are on a Thursday, Memorial Day is on May 27, Labor Day is on September 2, Thanksgiving is on its latest possible date, November 28, and Christmas is on a Wednesday.
Calendars[edit]
Calendar for any leap year starting on Monday,
presented as common in many English-speaking areas |
|
January |
|
| Su |
Mo |
Tu |
We |
Th |
Fr |
Sa |
|
1 |
2 |
3 |
4 |
5 |
6 |
| 7 |
8 |
9 |
10 |
11 |
12 |
13 |
| 14 |
15 |
16 |
17 |
18 |
19 |
20 |
| 21 |
22 |
23 |
24 |
25 |
26 |
27 |
| 28 |
29 |
30 |
31 |
|
|
|
|
February |
|
| Su |
Mo |
Tu |
We |
Th |
Fr |
Sa |
|
|
|
|
1 |
2 |
3 |
| 4 |
5 |
6 |
7 |
8 |
9 |
10 |
| 11 |
12 |
13 |
14 |
15 |
16 |
17 |
| 18 |
19 |
20 |
21 |
22 |
23 |
24 |
| 25 |
26 |
27 |
28 |
29 |
|
|
|
|
|
March |
|
| Su |
Mo |
Tu |
We |
Th |
Fr |
Sa |
|
|
|
|
|
1 |
2 |
| 3 |
4 |
5 |
6 |
7 |
8 |
9 |
| 10 |
11 |
12 |
13 |
14 |
15 |
16 |
| 17 |
18 |
19 |
20 |
21 |
22 |
23 |
| 24 |
25 |
26 |
27 |
28 |
29 |
30 |
| 31 |
|
|
|
April |
|
| Su |
Mo |
Tu |
We |
Th |
Fr |
Sa |
|
1 |
2 |
3 |
4 |
5 |
6 |
| 7 |
8 |
9 |
10 |
11 |
12 |
13 |
| 14 |
15 |
16 |
17 |
18 |
19 |
20 |
| 21 |
22 |
23 |
24 |
25 |
26 |
27 |
| 28 |
29 |
30 |
|
|
|
|
|
May |
|
| Su |
Mo |
Tu |
We |
Th |
Fr |
Sa |
|
|
|
1 |
2 |
3 |
4 |
| 5 |
6 |
7 |
8 |
9 |
10 |
11 |
| 12 |
13 |
14 |
15 |
16 |
17 |
18 |
| 19 |
20 |
21 |
22 |
23 |
24 |
25 |
| 26 |
27 |
28 |
29 |
30 |
31 |
|
|
|
|
June |
|
| Su |
Mo |
Tu |
We |
Th |
Fr |
Sa |
|
|
|
|
|
|
1 |
| 2 |
3 |
4 |
5 |
6 |
7 |
8 |
| 9 |
10 |
11 |
12 |
13 |
14 |
15 |
| 16 |
17 |
18 |
19 |
20 |
21 |
22 |
| 23 |
24 |
25 |
26 |
27 |
28 |
29 |
| 30 |
|
|
|
|
July |
|
| Su |
Mo |
Tu |
We |
Th |
Fr |
Sa |
|
1 |
2 |
3 |
4 |
5 |
6 |
| 7 |
8 |
9 |
10 |
11 |
12 |
13 |
| 14 |
15 |
16 |
17 |
18 |
19 |
20 |
| 21 |
22 |
23 |
24 |
25 |
26 |
27 |
| 28 |
29 |
30 |
31 |
|
|
|
|
August |
|
| Su |
Mo |
Tu |
We |
Th |
Fr |
Sa |
|
|
|
|
1 |
2 |
3 |
| 4 |
5 |
6 |
7 |
8 |
9 |
10 |
| 11 |
12 |
13 |
14 |
15 |
16 |
17 |
| 18 |
19 |
20 |
21 |
22 |
23 |
24 |
| 25 |
26 |
27 |
28 |
29 |
30 |
31 |
|
|
|
September |
|
| Su |
Mo |
Tu |
We |
Th |
Fr |
Sa |
| 1 |
2 |
3 |
4 |
5 |
6 |
7 |
| 8 |
9 |
10 |
11 |
12 |
13 |
14 |
| 15 |
16 |
17 |
18 |
19 |
20 |
21 |
| 22 |
23 |
24 |
25 |
26 |
27 |
28 |
| 29 |
30 |
|
|
|
|
|
October |
|
| Su |
Mo |
Tu |
We |
Th |
Fr |
Sa |
|
|
1 |
2 |
3 |
4 |
5 |
| 6 |
7 |
8 |
9 |
10 |
11 |
12 |
| 13 |
14 |
15 |
16 |
17 |
18 |
19 |
| 20 |
21 |
22 |
23 |
24 |
25 |
26 |
| 27 |
28 |
29 |
30 |
31 |
|
|
|
|
November |
|
| Su |
Mo |
Tu |
We |
Th |
Fr |
Sa |
|
|
|
|
|
1 |
2 |
| 3 |
4 |
5 |
6 |
7 |
8 |
9 |
| 10 |
11 |
12 |
13 |
14 |
15 |
16 |
| 17 |
18 |
19 |
20 |
21 |
22 |
23 |
| 24 |
25 |
26 |
27 |
28 |
29 |
30 |
|
|
|
|
December |
|
| Su |
Mo |
Tu |
We |
Th |
Fr |
Sa |
| 1 |
2 |
3 |
4 |
5 |
6 |
7 |
| 8 |
9 |
10 |
11 |
12 |
13 |
14 |
| 15 |
16 |
17 |
18 |
19 |
20 |
21 |
| 22 |
23 |
24 |
25 |
26 |
27 |
28 |
| 29 |
30 |
31 |
|
|
|
ISO 8601-conformant calendar with week numbers for
any leap year starting on Monday (dominical letter GF) |
|
January |
|
| Wk |
Mo |
Tu |
We |
Th |
Fr |
Sa |
Su |
| 01 |
01 |
02 |
03 |
04 |
05 |
06 |
07 |
| 02 |
08 |
09 |
10 |
11 |
12 |
13 |
14 |
| 03 |
15 |
16 |
17 |
18 |
19 |
20 |
21 |
| 04 |
22 |
23 |
24 |
25 |
26 |
27 |
28 |
| 05 |
29 |
30 |
31 |
|
|
|
|
|
February |
|
| Wk |
Mo |
Tu |
We |
Th |
Fr |
Sa |
Su |
| 05 |
|
|
|
01 |
02 |
03 |
04 |
| 06 |
05 |
06 |
07 |
08 |
09 |
10 |
11 |
| 07 |
12 |
13 |
14 |
15 |
16 |
17 |
18 |
| 08 |
19 |
20 |
21 |
22 |
23 |
24 |
25 |
| 09 |
26 |
27 |
28 |
29 |
|
|
|
|
|
|
|
March |
|
| Wk |
Mo |
Tu |
We |
Th |
Fr |
Sa |
Su |
| 09 |
|
|
|
|
01 |
02 |
03 |
| 10 |
04 |
05 |
06 |
07 |
08 |
09 |
10 |
| 11 |
11 |
12 |
13 |
14 |
15 |
16 |
17 |
| 12 |
18 |
19 |
20 |
21 |
22 |
23 |
24 |
| 13 |
25 |
26 |
27 |
28 |
29 |
30 |
31 |
|
|
|
|
April |
|
| Wk |
Mo |
Tu |
We |
Th |
Fr |
Sa |
Su |
| 14 |
01 |
02 |
03 |
04 |
05 |
06 |
07 |
| 15 |
08 |
09 |
10 |
11 |
12 |
13 |
14 |
| 16 |
15 |
16 |
17 |
18 |
19 |
20 |
21 |
| 17 |
22 |
23 |
24 |
25 |
26 |
27 |
28 |
| 18 |
29 |
30 |
|
|
|
|
|
|
May |
|
| Wk |
Mo |
Tu |
We |
Th |
Fr |
Sa |
Su |
| 18 |
|
|
01 |
02 |
03 |
04 |
05 |
| 19 |
06 |
07 |
08 |
09 |
10 |
11 |
12 |
| 20 |
13 |
14 |
15 |
16 |
17 |
18 |
19 |
| 21 |
20 |
21 |
22 |
23 |
24 |
25 |
26 |
| 22 |
27 |
28 |
29 |
30 |
31 |
|
|
|
|
|
June |
|
| Wk |
Mo |
Tu |
We |
Th |
Fr |
Sa |
Su |
| 22 |
|
|
|
|
|
01 |
02 |
| 23 |
03 |
04 |
05 |
06 |
07 |
08 |
09 |
| 24 |
10 |
11 |
12 |
13 |
14 |
15 |
16 |
| 25 |
17 |
18 |
19 |
20 |
21 |
22 |
23 |
| 26 |
24 |
25 |
26 |
27 |
28 |
29 |
30 |
|
|
|
|
July |
|
| Wk |
Mo |
Tu |
We |
Th |
Fr |
Sa |
Su |
| 27 |
01 |
02 |
03 |
04 |
05 |
06 |
07 |
| 28 |
08 |
09 |
10 |
11 |
12 |
13 |
14 |
| 29 |
15 |
16 |
17 |
18 |
19 |
20 |
21 |
| 30 |
22 |
23 |
24 |
25 |
26 |
27 |
28 |
| 31 |
29 |
30 |
31 |
|
|
|
|
|
August |
|
| Wk |
Mo |
Tu |
We |
Th |
Fr |
Sa |
Su |
| 31 |
|
|
|
01 |
02 |
03 |
04 |
| 32 |
05 |
06 |
07 |
08 |
09 |
10 |
11 |
| 33 |
12 |
13 |
14 |
15 |
16 |
17 |
18 |
| 34 |
19 |
20 |
21 |
22 |
23 |
24 |
25 |
| 35 |
26 |
27 |
28 |
29 |
30 |
31 |
|
|
|
|
|
September |
|
| Wk |
Mo |
Tu |
We |
Th |
Fr |
Sa |
Su |
| 35 |
|
|
|
|
|
|
01 |
| 36 |
02 |
03 |
04 |
05 |
06 |
07 |
08 |
| 37 |
09 |
10 |
11 |
12 |
13 |
14 |
15 |
| 38 |
16 |
17 |
18 |
19 |
20 |
21 |
22 |
| 39 |
23 |
24 |
25 |
26 |
27 |
28 |
29 |
| 40 |
30 |
|
|
|
|
October |
|
| Wk |
Mo |
Tu |
We |
Th |
Fr |
Sa |
Su |
| 40 |
|
01 |
02 |
03 |
04 |
05 |
06 |
| 41 |
07 |
08 |
09 |
10 |
11 |
12 |
13 |
| 42 |
14 |
15 |
16 |
17 |
18 |
19 |
20 |
| 43 |
21 |
22 |
23 |
24 |
25 |
26 |
27 |
| 44 |
28 |
29 |
30 |
31 |
|
|
|
|
|
November |
|
| Wk |
Mo |
Tu |
We |
Th |
Fr |
Sa |
Su |
| 44 |
|
|
|
|
01 |
02 |
03 |
| 45 |
04 |
05 |
06 |
07 |
08 |
09 |
10 |
| 46 |
11 |
12 |
13 |
14 |
15 |
16 |
17 |
| 47 |
18 |
19 |
20 |
21 |
22 |
23 |
24 |
| 48 |
25 |
26 |
27 |
28 |
29 |
30 |
|
|
|
|
|
December |
|
| Wk |
Mo |
Tu |
We |
Th |
Fr |
Sa |
Su |
| 48 |
|
|
|
|
|
|
01 |
| 49 |
02 |
03 |
04 |
05 |
06 |
07 |
08 |
| 50 |
09 |
10 |
11 |
12 |
13 |
14 |
15 |
| 51 |
16 |
17 |
18 |
19 |
20 |
21 |
22 |
| 52 |
23 |
24 |
25 |
26 |
27 |
28 |
29 |
| 01 |
30 |
31 |
|
|
Applicable years[edit]
Gregorian Calendar[edit]
Leap years that begin on Monday, along with those that start on Saturday or Thursday, occur least frequently: 13 out of 97 (≈ 13.402%) total leap years of the Gregorian calendar. Their overall occurrence is thus 3.25% (13 out of 400).
Gregorian leap years starting on Monday[1]
| Decade |
1st |
2nd |
3rd |
4th |
5th |
6th |
7th |
8th |
9th |
10th |
| 17th century |
|
|
1624 |
|
|
1652 |
|
1680 |
|
|
| 18th century |
|
1720 |
|
|
1748 |
|
|
1776 |
|
|
| 19th century |
|
1816 |
|
|
1844 |
|
|
1872 |
|
|
| 20th century |
|
1912 |
|
|
1940 |
|
1968 |
|
|
1996 |
| 21st century |
|
|
2024 |
|
|
2052 |
|
|
2080 |
|
| 22nd century |
|
2120 |
|
|
2148 |
|
|
2176 |
|
|
| 23rd century |
|
2216 |
|
|
2244 |
|
|
2272 |
|
|
| 24th century |
|
2312 |
|
2340 |
|
|
2368 |
|
|
2396 |
| 25th century |
|
|
2424 |
|
|
2452 |
|
2480 |
|
|
| 26th century |
|
2520 |
|
|
2548 |
|
|
2576 |
|
|
Gregorian year types per leap cycle by Dominical letter (DL)[2] and Doomsday (DD)
| Year starts |
|
Common years |
|
Leap years |
| 1 Jan |
Count |
Ratio |
31 Dec |
DL |
DD |
Count |
Ratio |
31 Dec |
DL |
DD |
Count |
Ratio |
| Sun |
58 |
14.50 % |
Sun |
A |
Tue |
43 |
10.75 % |
Mon |
AG |
Wed |
15 |
3.75 % |
| Sat |
56 |
14.00 % |
Sat |
B |
Mon |
43 |
10.75 % |
Sun |
BA |
Tue |
13 |
3.25 % |
| Fri |
58 |
14.50 % |
Fri |
C |
Sun |
43 |
10.75 % |
Sat |
CB |
Mon |
15 |
3.75 % |
| Thu |
57 |
14.25 % |
Thu |
D |
Sat |
44 |
11.00 % |
Fri |
DC |
Sun |
13 |
3.25 % |
| Wed |
57 |
14.25 % |
Wed |
E |
Fri |
43 |
10.75 % |
Thu |
ED |
Sat |
14 |
3.50 % |
| Tue |
58 |
14.50 % |
Tue |
F |
Thu |
44 |
11.00 % |
Wed |
FE |
Fri |
14 |
3.50 % |
| Mon |
56 |
14.00 % |
Mon |
G |
Wed |
43 |
10.75 % |
Tue |
GF |
Thu |
13 |
3.25 % |
| ∑ |
400 |
100.0 % |
|
303 |
75.75 % |
|
97 |
24.25 % |
Julian Calendar[edit]
Like all leap year types, the one starting with 1 January on a Monday 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 Monday
| Decade |
1st |
2nd |
3rd |
4th |
5th |
6th |
7th |
8th |
9th |
10th |
| 14th century |
1308 |
|
|
1336 |
|
|
1364 |
|
|
1392 |
| 15th century |
|
1420 |
|
|
1448 |
|
|
1476 |
|
|
| 16th century |
1504 |
|
|
1532 |
|
1560 |
|
|
1588 |
|
| 17th century |
|
1616 |
|
|
1644 |
|
|
1672 |
|
1700 |
| 18th century |
|
|
1728 |
|
|
1756 |
|
|
1784 |
|
| 19th century |
|
1812 |
|
1840 |
|
|
1868 |
|
|
1896 |
| 20th century |
|
|
1924 |
|
|
1952 |
|
1980 |
|
|
| 21st century |
2008 |
|
|
2036 |
|
|
2064 |
|
|
2092 |
| 22nd century |
|
2120 |
|
|
2148 |
|
|
2176 |
|
|
