*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19721
19730
19740
19750
19760
19770
19780
19790
19800
19810
19821
19830
19841
19850
19863
19874
19882
19894
19901
19918
19920
19932
19941
19958
19960
19970
19980
19990
20000
20010
20029
20032
20040
20050
20060
20070
20080
20090
20101
20110
20120
20130
20140
20150
20160
20170
20180
20191
20200
Total49