*Excludes Observations that spanned multiple years

Pre 19704
19700
19710
197213
19733
19740
19750
19761
19770
19780
19790
19800
19810
19820
19830
19840
19855
19860
198712
19883
19893
199019
19914
199211
19932
19941
19952
19960
19970
19980
19990
20000
20011
20020
20031
20041
20050
20060
20070
20080
20090
20100
20112
20120
20130
20140
20151
20160
20171
20180
20190
Total90