*Excludes Observations that span multiple months

  B
b
t
W
w
 
Jan00115860
Feb002301639
Mar07920099
Apr01028100291
May610458500695
Jun47183803001033
Jul531917100243
Aug839500106
Sep1210000103
Oct0013400134
Nov00650065
Dec00280216244
Total115328237812903112