*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970100001
1970000000
1971000000
1972000000
1973100001
1974000000
1975000000
1976000000
1977000000
1978000101
1979000000
1980100001
1981000404
1982000404
1983000303
1984100203
1985000000
1986000000
1987000101
1988000000
1989100001
1990000000
1991000505
1992100203
1993200406
1994200002
1995200204
1996200305
1997100102
1998100001
1999300609
2000100809
2001000808
2002100708
2003200204
2004300205
2005300104
20062008010
2007500207
20083106010
200910022023
201010059060
201110085086
201260061067
201330032035
2014000101
2015000000
2016000000
2017000000
2018000000
Total51103420394