*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000000
1970000000
1971000000
1972000000
1973000000
1974000000
1975000000
1976000000
1977000000
1978000101
1979000000
1980000202
1981000202
1982000000
1983000000
1984000000
1985000000
1986000112
1987000011
1988000303
1989000279
1990000011
1991000314
1992000011
1993000011
1994000235
1995000000
1996000000
1997000123
1998000145
1999000000
2000000011
2001000101
2002000213
2003000011
2004000202
2005000279
2006000415
2007000257
2008000101
2009000033
2010000404
2011000134
201200011819
2013000123
2014000000
2015000101
2016000000
2017000000
2018000000
Total0004064104