*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970200406
1970000101
1971100001
1972000000
1973000000
1974000000
1975000202
1976000202
1977000505
1978000000
1979000606
1980000505
1981000202
1982000202
1983000000
1984000000
1985100304
19860018312
19872019012
1988001629
198910211418
199000462838
1991008121232
199200012416
1993003142037
1994201285586
1995004192851
1996205213159
19970062481111
1998302276294
1999002233459
2000200226791
20012042481111
2002101366098
200300266111179
200400131108140
200500487104195
200600472146222
20070007843121
200800211014126
200910114066208
201000320362268
201100033323356
201200023437271
201300010220122
201400011819
201500019322
2016000123
2017000314
2018000000
Total20062182413203226