Gregorian - Sunday-based week with week numbers
      August 2006             September 2006            October 2006     
   Su Mo Tu We Th Fr Sa     Su Mo Tu We Th Fr Sa     Su Mo Tu We Th Fr Sa
31        1  2  3  4  5  35                 1  2  40  1  2  3  4  5  6  7
32  6  7  8  9 10 11 12  36  3  4  5  6  7  8  9  41  8  9 10 11 12 13 14
33 13 14 15 16 17 18 19  37 10 11 12 13 14 15 16  42 15 16 17 18 19 20 21
34 20 21 22 23 24 25 26  38 17 18 19 20 21 22 23  43 22 23 24 25 26 27 28
35 27 28 29 30 31        39 24 25 26 27 28 29 30  44 29 30 31