*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970503008
1970100001
1971100001
1972100001
1973002002
1974000000
1975100001
1976000000
1977002002
1978100001
1979103004
1980102003
1981100001
1982102003
1983101002
1984101002
1985202004
1986104005
1987106007
1988104005
1989017008
199000110011
199131110015
199200100010
199321270030
199450290034
199530200124
199621260029
199723450050
199830300033
199940160020
200030240027
200130340037
200211320034
200312450048
200410530054
200501660067
200600340034
200700490049
200811400042
200970580065
2010409600100
201140910095
201200520052
201300160016
2014006006
2015009009
2016002002
2017000000
Total7012971011054