*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19851
19860
19871
19882
19890
19900
19910
19923
19933
19940
19951
19960
19971
19983
19990
20001
20010
20021
20031
20040
20050
20060
20070
20081
20090
20102
20110
20121
20130
20140
20151
20160
20170
20182
20191
20201
20211
20220
20230
20240
Total28