*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19861
19873
19880
19891
19900
19912
19922
199310
199416
19953
19960
19970
19983
19991
20000
20011
20020
20030
20040
20050
20061
20070
200810
20090
20100
20110
20120
20130
20141
20150
20160
20170
Total55