*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000000
1970000000
1971000000
1972000000
1973000101
1974000000
1975000000
1976000101
1977000000
1978000101
1979000000
1980000000
1981000000
1982000000
1983000000
1984000000
1985000000
1986000000
1987000000
1988000101
1989000000
1990000000
1991000000
1992000000
1993000000
1994000000
1995000101
1996000000
1997000000
1998000000
1999000101
2000000101
2001000101
2002000000
2003000000
2004000000
2005000101
2006000101
2007000000
2008000101
2009000101
2010000303
2011000303
2012000202
2013000101
2014000000
2015000101
2016000000
2017000000
2018000000
Total00022022