*Excludes Observations that span multiple months

  B
b
t
W
w
 
Jan00005353
Feb001501631
Mar6154600553
Apr3322865002900
May271482928003103
Jun721261800001998
Jul49631100366
Aug8247600486
Sep0139800399
Oct0037100371
Nov0013900139
Dec00201109130
Total1653169869117810529