*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19781
19790
19801
19811
19820
19832
19841
19850
19860
19871
198836
19891
19901
199140
199211
199343
19940
199510
19960
19970
19980
19990
20000
20016
20023
20032
20041
20051
20064
20070
20086
20090
20100
20118
20122
20137
20141
20151
20167
201722
201825
201938
202020
202128
202236
202347
20240
Total414