*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970005308
1970001001
1971001001
1972001001
1973000202
1974000000
1975001001
1976000000
1977000202
1978001001
1979001304
1980001203
1981001001
1982001203
1983001102
1984001102
1985002204
1986001405
1987001607
1988001405
1989000718
199000011011
199100311115
199200010010
199300227130
199400529034
199510320024
199600226129
199700245350
199800330033
199900416020
200000324027
200100334037
200200132134
200300145248
200400153054
200500066167
200600034034
200700049049
200800140142
200900758065
2010004960100
201100491095
201200052052
201300016016
2014000606
2015000909
2016000202
2017000000
2018000000
Total1070971121054