*Excludes Observations that spanned multiple years

Pre 19706
19701
19710
19720
19730
19740
19750
19761
19770
19780
19790
19800
19810
19820
19830
19841
19850
19860
19870
19880
19897
19900
19916
19920
19934
19940
19951
19960
19972
19981
19990
20000
20010
20020
20030
20040
20050
20060
20070
20080
20090
20100
20111
20120
20132
20141
20150
20160
20170
20180
20190
20200
20210
Total34