*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000011
1970000000
1971000000
1972000000
1973000000
1974000000
1975000000
1976000000
1977000000
1978000011
1979000000
1980000000
1981000000
1982000011
1983000000
1984000033
1985001023
1986000011
1987000134
1988001124
1989000011
1990001045
199100110314
199200120517
1993004048
1994003047
19950040610
19960080311
19970040812
1998003047
1999002046
2000001045
2001003058
20020070411
2003007029
20040040812
20050030811
2006002057
20070031610
20080030811
2009001012
2010001034
20110061310
2012003069
2013001001
2014000000
2015001001
2016000011
2017001001
Total001014124229