We have some variety this week.

8/18/13 is the Half-back Day of the month.  8 to 18 is 10, and then 18 to 13 is half way back.

8/21/13 is a backwards subtraction day;  21-8 = 13.

AND, we have the last All Fibonacci numbers day, 8/21/13, until the year 2021.  Enjoy!