*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970201205
1970000000
1971000000
1972000000
1973000000
1974000000
1975000000
1976000000
1977000000
1978000101
1979000101
1980100001
1981100001
1982000000
1983000213
1984000000
1985000101
1986001405
1987002608
1988000516
1989001506
199020112419
199110423230
199200310114
199300321226
199400121426
199510732242
199600415322
199710122226
19980019414
199900111214
200010211317
200110314422
200200014317
200310420025
200400015116
200500217221
200610217323
200700014014
200800120021
200900984093
201000101624176
20110061922200
20122081700180
201300085085
201400224026
201500116017
2016001113
2017000000
2018000000
Total150821079511227