Gregorian - Monday-based year with weeks
   January 2147483646  
   Mo Tu We Th Fr Sa Su
 1  1  2  3  4  5  6  7
 2  8  9 10 11 12 13 14
 3 15 16 17 18 19 20 21
 4 22 23 24 25 26 27 28
 5 29 30 31