*Excludes Observations that spanned multiple years

Pre 19701
19700
19710
19720
19733
19740
19750
19760
19770
19781
19790
19800
19810
19820
19830
19841
19850
19860
19871
19883
19890
19902
19910
19923
19932
19945
19954
19962
19970
19983
19990
20001
20012
20020
20031
20040
20052
20061
20072
20080
20094
20107
20119
20128
201315
20144
20157
20168
20174
201816
20191
20200
20212
20220
20236
20240
Total131