*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 197023039035
1970100102
1971700007
1972300003
1973300003
1974400004
1975200002
1976500106
19776034720
1978401511030
197920376853
198040512259
198150142324
19827012010
1983500207
198411022015
1985601209
19869003012
198713017021
198814033020
19898006115
19909104115
199150027335
199280014022
1993100019231
1994170020239
1995171022141
199690022233
1997131134150
199870225236
1999130539259
2000140250773
2001190032354
2002120140154
2003150534357
2004180023243
2005160119137
2006170312133
2007160225144
2008144242466
2009100233146
201060246054
2011130085199
2012300023154
201340120025
2014000639
201530016120
20162008010
2017200204
2018000000
Total4617160795771500