*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 197020014016
1970000404
1971000101
1972000000
1973000000
1974000101
1975000000
1976000000
1977100001
1978000000
1979000000
1980000101
1981000101
1982000101
1983000101
1984000000
1985000000
1986000000
1987000000
1988100001
1989000202
1990000101
1991000303
1992100203
1993100203
1994300205
19954007011
1996100304
1997000404
1998100001
1999300003
2000100708
2001100203
2002000202
2003600107
2004200406
2005100001
2006200305
20073008011
2008100304
2009100405
2010010102
2011200406
2012100102
2013000101
2014000101
2015000000
2016000000
2017000000
2018000000
Total3910920132