*Excludes Observations that spanned multiple years

Pre 19704
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19801
19810
19820
19830
19840
19852
19860
19870
19880
19891
19900
19910
19921
19930
19941
19950
19961
19974
19982
19991
20000
20011
20020
20031
20040
20050
20061
20070
20080
20091
20100
20112
20120
20130
20140
20150
20160
20170
20180
20190
20200
Total24