*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19729
19731
19740
19750
19760
19770
19780
19791
19801
19810
19820
19830
19841
19859
19862
19877
19886
19894
199011
199136
199216
199318
19942
19955
19961
19970
19981
19990
20000
20011
20023
20030
20040
20050
20060
20070
20080
20090
20100
20111
20120
20130
20140
20150
20160
20173
20182
20190
20200
Total141