*Excludes Observations that span multiple months

  B
b
t
W
w
 
Jan00002424
Feb004026
Mar00750075
Apr511070001076
May2472173002204
Jun5532633002691
Jul1821750001770
Aug601150001156
Sep1065600657
Oct0020700207
Nov00570057
Dec001204860
Total1091397870749983