In any given year, there are 15 weeks between the two dates.
18 weeks
Between August 14 2009 and December 8, 2009 there were 16 weeks and 4 days.
21 weeks
Weeks from August 30 to December 31 2010 is slightly over 17.
19 weeks and 4 days.
Nearly 22 weeks.
About 78 weeks between June 2009 and December 2010.
There are 56.5 weeks between August 1, 2011 and August 31, 2012.
104.4 weeks
574 weeks
260 weeks and 6 days.
313 weeks.