*Excludes Observations that span multiple months

  B
b
t
W
w
 
Jan0001638639
Feb0756714411016
Mar1612450002512
Apr21224585004709
May14102229580011194
Jun891630812140017611
Jul7518213976005872
Aug591395001409
Sep0487100875
Oct0060300603
Nov0016700167
Dec001030700803
Total18628554168892177947410