*Excludes Observations that span multiple months

  B
b
t
W
w
 
Jan00005858
Feb035403087
Mar03410600140
Apr031357700890
May299529800422
Jun1573244100630
Jul1111727900407
Aug28627000304
Sep8214900159
Oct1011300114
Nov00950095
Dec002914272
Total334502241111303378