*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000000
1970000000
1971000000
1972000000
1973000000
1974000000
1975000000
1976000000
1977001001
1978000000
1979000000
1980000000
1981001001
1982000000
1983000000
1984000000
1985003003
1986000000
1987102003
1988206008
1989016007
1990105006
19913160010
199200100010
1993105006
199411100012
1995211150028
19961270010
199742170023
199822130017
199903120015
200011100012
200140140018
200201160017
200311230025
200410160017
200510110012
200610180019
200710260027
200800270027
200900240024
201000300030
201110360037
201200180018
201300180018
2014000000
2015103004
2016002002
2017000000
Total302641100467