*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 19701460011
1970000000
1971000000
1972000000
1973001001
1974001001
1975000000
1976000000
1977021003
1978000000
1979000000
1980001001
1981000000
1982001001
1983010001
1984000000
1985000000
1986000000
1987021003
1988001001
1989000000
1990011002
1991001001
1992022004
1993010001
199401030013
199511510017
199601610017
1997060006
1998050005
1999070007
2000030003
2001001023
2002025007
2003035008
200401100011
2005071008
2006001001
2007000000
2008000000
2009000000
2010010001
2011000000
2012000000
2013000000
2014000000
2015000000
2016000000
2017000000
Total2993502138