*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19841
19850
19861
19871
19880
19892
199013
199113
19921
19931
19940
19951
19960
19970
19980
19990
20000
20010
20020
20030
20040
20050
20060
20070
20080
20091
20103
20115
20121
20131
20141
20151
20161
20171
20180
Total49