*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000303
1970000101
1971000000
1972000000
1973000000
1974000000
1975000303
1976000101
1977000202
1978000000
1979000000
1980000000
1981000101
1982000303
1983000000
1984000303
1985000202
1986000224
198700114419
198800019019
198900021425
199000022022
199100341320
19920017189197
19930035398406
19940031610071026
199500011674685
19960026792800
19970018347356
19980002725727
199900013168181
200000012939951
200100014474488
200200011621632
200300117419437
20040006756762
200500117294312
200600216293311
200700132438471
200800020237257
2009001342459
201000181246328
20110007155126
20120024116122
201300536243284
201400017133150
201500111214
2016000066
2017000011
2018000000
Total0029548964010217