*Excludes Observations that spanned multiple years

Pre 19706
19700
19710
19721
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19831
19840
19851
19860
19870
19880
19890
19900
19913
19921
19933
19940
19951
19961
19970
19981
19991
20001
20010
20020
20030
20040
20050
20060
20075
20080
20092
20100
20110
20121
20130
20140
20151
20160
20170
20180
20190
20200
20210
Total30