*Excludes Observations that spanned multiple years

Pre 19702
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19815
19820
19832
19841
19851
19860
19871
19881
19890
19905
199112
19924
19939
19941
19952
19964
19970
19980
19990
20000
20010
20022
20030
20040
20050
20060
20071
20080
20090
20100
20111
20121
20133
20142
20150
20160
20170
20180
Total60