*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
1985000000
1986000000
1987000000
1988000000
1989000000
1990000000
1991000000
1992000000
1993000000
1994000000
1995000202
1996001012
1997000011
1998000000
1999001012
2000002002
2001003003
2002000347
2003001135
2004001135
2005000101
2006000022
2007000303
2008000202
2009000101
2010000000
2011000213
2012000000
2013000033
2014000235
2015000112
2016000000
2017000000
2018000000
Total009202352