*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19731
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19861
19872
19884
19897
19902
19910
19921
19932
19941
19950
19963
19975
19980
19990
20003
20011
20024
20030
20040
20052
20061
20070
20080
20090
20101
20110
20121
20131
20140
20150
20160
20171
20180
20190
Total44