*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19851
19861
19870
19880
19891
19900
19911
19920
19932
199413
19958
19960
19971
19980
19990
20000
20010
20023
20037
20041
20050
20060
20070
20084
20090
20100
20110
20120
20130
20140
20150
20160
20170
Total43