*Excludes Observations that span multiple months

  B
b
t
W
w
 
Jan0002519321957
Feb1272577881523
Mar481214001226
Apr3161088001107
May105678171005859
Jun59134293480013836
Jul3945112601007151
Aug14292088002131
Sep161747001754
Oct001252001252
Nov0184000841
Dec00447218192268
Total131236801252134453940905