*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000303
1970000000
1971000000
1972000000
1973000000
1974000000
1975000101
1976000000
1977000101
1978000101
1979000404
1980000202
1981000101
1982000202
1983000000
1984000000
1985000000
1986000808
1987000606
1988000404
1989000707
1990000909
199100025025
199200018018
199300021021
199400021021
199500024024
199600019019
199700019019
199800014014
199900017017
200000017017
200100018018
200200024024
200300030030
200400019019
200500016016
200600019019
200700020020
200800022022
200900040040
201000028028
201100026026
201200022022
2013000606
2014000303
2015000303
2016000000
2017000101
2018000000
Total0005410541