*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 197020115018
1970000000
1971100001
1972000000
1973100001
1974000202
1975000000
1976000000
1977000000
1978000303
1979000101
1980000101
1981000000
1982100001
1983000000
1984000415
1985001113
1986200327
1987001315
1988200114
19892009213
1990000628
199120310419
199200111214
1993103239
19941049216
19952008313
199610211115
199720021225
199810213420
199920215221
20004029116
200110413119
200200214420
20032065417
200440210218
20052007211
200610510319
20072022511
2008100416
20090067316
201000511824
201120517428
2012100315
201340012117
2014101349
201500310215
20160027110
20170046010
2018000000
Total4806929980496