*Excludes Observations that spanned multiple years

Pre 19703
19700
19710
19720
19731
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19841
19851
19860
19870
19881
19890
19901
19911
19921
19931
19945
19950
19960
19970
19980
19990
20001
20010
20021
20030
20040
20050
20063
20074
20081
20090
20100
20110
20120
20132
20140
20150
20160
20170
20180
Total28