*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000000
1970000000
1971000000
1972000000
1973000000
1974000000
1975000000
1976000000
1977000101
1978000000
1979000101
1980000000
1981000000
1982000000
1983000000
1984000101
1985000202
1986000303
1987000303
1988000000
1989000303
1990000303
199100011011
1992000808
1993000303
1994000202
199500011011
199600010010
199700010010
1998000606
199900011011
2000000707
2001000404
200200010010
2003000808
2004000808
2005000505
2006000606
2007000909
200800012012
200900014014
201000020020
201100016016
201200017017
201300010010
2014000202
2015000000
2016000000
2017000000
2018000000
Total0002370237