*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000000
1970000000
1971000000
1972000000
1973000000
1974000000
1975000000
1976000000
1977000101
1978000000
1979000000
1980000000
1981000101
1982000000
1983000000
1984000000
1985000303
1986000000
1987001203
1988002608
1989000617
1990001506
19910036110
199200010010
1993001506
199400110112
1995002151128
19960017210
199700417223
199800213217
199900012315
200000110112
200100414018
200200016117
200300123125
200400116017
200500111012
200600118019
200700126027
200800027027
200900024024
201000030030
201100136037
201200018018
201300018018
2014000000
2015001304
2016000202
2017000000
2018000000
Total003041126467