*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000505
1970000000
1971000000
1972000000
1973000202
1974000202
1975000000
1976000000
1977000000
1978000000
1979000000
1980000202
1981000101
1982000000
1983000202
1984000000
1985000000
1986000000
1987000000
1988000000
1989000000
1990000000
1991000000
1992000101
1993000202
1994000303
1995000404
1996000000
1997000000
1998000000
1999000000
2000000000
2001000101
2002000000
2003000000
2004000101
2005000000
2006000000
2007000000
2008000505
2009000303
2010000000
2011000303
2012000101
2013000000
2014000101
2015000101
2016000000
2017000000
2018000000
Total00040040