*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 197010202023
1970000011
1971000011
1972000022
1973000022
1974001012
1975002035
1976001168
1977000167
1978000044
1979001034
1980000044
1981000044
1982001056
1983000088
1984001034
1985001045
1986001056
1987003047
19880140813
1989003069
19900110911
19910071513
1992004059
19930060713
199401110921
1995004059
19961060512
1997022037
19980050510
19990050510
20000090615
200100100515
20020180110
2003004026
20040350715
20050670215
2006005038
20071091617
200800130720
200900120315
201000230528
2011002001030
201220151826
2013000033
2014012003
2015002024
2016005016
2017000011
Total5162215230477