*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970003003
1970000000
1971000000
1972000000
1973000000
1974000000
1975000000
1976001001
1977000000
1978000000
1979000000
1980000000
1981000000
1982000000
1983000000
1984000000
1985001001
1986000000
1987000000
1988000000
1989000000
1990000000
1991000000
1992001001
1993000000
1994000000
1995000000
1996000000
1997000000
1998000000
1999001001
2000000000
2001001001
2002000000
2003000000
2004000000
2005001001
2006000000
2007002002
2008001001
2009001001
2010000000
2011002002
2012000000
2013001001
2014000000
2015000000
2016000000
2017001001
Total00170017