*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19862
19870
19881
19891
19902
19910
19922
19930
19940
19950
19960
19971
19980
19990
20000
20010
20020
20031
20040
20050
20060
20071
20080
20090
20100
20110
20121
20130
20140
20151
20161
20171
20181
20190
Total16