*Excludes Observations that spanned multiple years

Pre 19701
19700
19710
19720
19730
19740
19751
19760
19770
19781
19790
19800
19811
19821
19832
19841
19852
198610
198718
198841
198920
199012
199110
199227
199335
199417
199511
199611
199729
199811
19996
20001
20012
200214
20036
200429
200512
20065
20075
200812
20090
201013
20118
20122
20131
20140
20156
201610
201718
20184
Total416