*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19791
19800
19810
19820
19830
19840
19850
19867
19870
19881
19894
19901
19910
19920
19938
19941
19951
19961
19970
19980
19990
20000
20010
20021
20030
20041
20050
20060
20070
20082
20090
20100
20111
20120
20131
20141
20150
20160
20171
20182
20190
20200
Total35