Leap year starting on Sunday - Definition and Overview

Here is a calendar for any leap year starting on Sunday (dominical letter AG).

2012 is such a year.

       January               February               March
 Su Mo Tu We Th Fr Sa  Su Mo Tu We Th Fr Sa  Su Mo Tu We Th Fr Sa
  1  2  3  4  5  6  7            1  2  3  4               1  2  3
  8  9 10 11 12 13 14   5  6  7  8  9 10 11   4  5  6  7  8  9 10
 15 16 17 18 19 20 21  12 13 14 15 16 17 18  11 12 13 14 15 16 17
 22 23 24 25 26 27 28  19 20 21 22 23 24 25  18 19 20 21 22 23 24
 29 30 31              26 27 28 29           25 26 27 28 29 30 31

        April                  May                   June
 Su Mo Tu We Th Fr Sa  Su Mo Tu We Th Fr Sa  Su Mo Tu We Th Fr Sa
  1  2  3  4  5  6  7         1  2  3  4  5                  1  2
  8  9 10 11 12 13 14   6  7  8  9 10 11 12   3  4  5  6  7  8  9
 15 16 17 18 19 20 21  13 14 15 16 17 18 19  10 11 12 13 14 15 16
 22 23 24 25 26 27 28  20 21 22 23 24 25 26  17 18 19 20 21 22 23</font>
 29 30                 27 28 29 30 31        24 25 26 27 28 29 30

         July                 August              September
 Su Mo Tu We Th Fr Sa  Su Mo Tu We Th Fr Sa  Su Mo Tu We Th Fr Sa
  1  2  3  4  5  6  7            1  2  3  4                     1
  8  9 10 11 12 13 14   5  6  7  8  9 10 11   2  3  4  5  6  7  8
 15 16 17 18 19 20 21  12 13 14 15 16 17 18   9 10 11 12 13 14 15
 22 23 24 25 26 27 28  19 20 21 22 23 24 25  16 17 18 19 20 21 22
 29 30 31              26 27 28 29 30 31     23 24 25 26 27 28 29
                                             30

       October               November              December
 Su Mo Tu We Th Fr Sa  Su Mo Tu We Th Fr Sa  Su Mo Tu We Th Fr Sa
     1  2  3  4  5  6               1  2  3                     1
  7  8  9 10 11 12 13   4  5  6  7  8  9 10   2  3  4  5  6  7  8
 14 15 16 17 18 19 20  11 12 13 14 15 16 17   9 10 11 12 13 14 15
 21 22 23 24 25 26 27  18 19 20 21 22 23 24  16 17 18 19 20 21 22
 28 29 30 31           25 26 27 28 29 30     23 24 25 26 27 28 29
                                             30 31

Previous year  Next year

Examples

2nd millennium AD
19th century
1804 1832 1860 1888

20th century
1928 1956 1984

3rd millennium AD
21st century
2012 2040 2068 2096

Common year starting on Sun - Mon - Tue - Wed - Thu - Fri - Sat
Leap year starting on   Sun - Mon - Tue - Wed - Thu - Fri - Sat