*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19731
19740
19750
19760
19770
19781
19790
19800
19810
19820
19830
19840
19850
19862
19871
19880
198910
19900
19912
19922
19930
19940
19950
19964
19970
19981
19990
20001
20013
20020
20030
20040
20050
20060
20071
20080
20090
20100
20110
20120
20131
20141
20150
20162
20171
20182
20190
20200
Total36