*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000000
1970000000
1971000000
1972000000
1973000000
1974000000
1975000000
1976000000
1977000101
1978000000
1979000000
1980000000
1981000000
1982000000
1983000000
1984000000
1985000101
1986000404
1987000404
1988000303
1989000404
1990000202
1991000909
1992000808
1993000606
1994000505
1995000707
1996000909
1997000404
1998000606
1999000808
2000000909
200100010010
2002000909
2003000404
2004000707
200500010010
2006000707
2007000606
2008000909
2009000808
2010000606
201100016016
2012000505
2013000404
2014000101
2015000101
2016000000
2017000000
2018000000
Total0001930193