9 * 9 = 81 = 3 char - single digit month, single digit day 22.5%
9 * 21 = 189 = 4 char - single digit month, double digit day 52.5%
3 * 9 = 27 = 4 char - double digit month, single digit day 7.5%
3 * 21 = 63 = 5 char - double digit month, double digit day 17.5%