*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000314
1970000000
1971000101
1972000000
1973000000
1974000000
1975000000
1976000000
1977000000
1978000000
1979000000
1980000101
1981000011
1982000000
1983000000
1984000000
1985000000
1986000000
1987000000
1988000000
1989000000
1990000112
1991000000
1992000000
1993000000
1994000101
1995000000
1996000000
1997000112
1998000000
1999000303
2000000101
2001000112
2002000415
2003000314
2004000112
2005000404
2006000156
20070004610
2008000202
2009000101
201000011011
2011000819
2012000055
2013000101
2014000202
2015000202
2016000000
2017000000
2018000000
Total000572582