*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000101
1970000000
1971000000
1972000000
1973000000
1974000000
1975000000
1976000000
1977000202
1978000000
1979000505
1980000202
1981000202
1982000202
1983000000
1984000000
1985000303
1986000606
1987000808
1988000909
198900010010
199000014014
199100019019
199200016016
199300020020
199400016016
199500035035
199600018018
199700022022
199800026026
199900014014
200000031031
200100046046
200200070070
200300034034
200400017017
200500018018
200600019019
200700034034
200800024024
200900048048
201000029029
201100051051
201200017017
201300016016
2014000202
2015000404
2016000000
2017000000
2018000000
Total0007100710