*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000101
1970000000
1971000000
1972000000
1973000000
1974000000
1975000101
1976000000
1977000101
1978000000
1979000000
1980000000
1981000202
1982000000
1983000000
1984000000
1985000000
1986000303
1987000808
1988000404
1989000101
1990000404
1991000707
1992000606
1993000404
199400011011
199500018018
199600014014
199700012012
1998000606
199900010010
200000019019
200100018018
200200021021
200300027027
2004000909
200500051051
2006000707
200700022022
200800013013
200900067067
201000038038
201100024024
201200041041
201300010010
2014000000
2015000404
2016000000
2017000000
2018000000
Total0004840484