*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19821
19830
19840
19850
19862
19871
19880
19891
19904
19911
19923
19930
19945
19955
19960
19976
19980
19990
20000
20014
20020
20030
20040
20050
20060
20070
20082
20090
201055
201129
20126
20138
20142
20152
20169
20171
20180
Total147