*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19871
19885
19890
19900
19910
19920
19932
19945
19950
19965
199715
19982
199916
200010
20010
20020
20033
20040
20052
20061
20070
20080
20090
201022
201110
20121
20131
20141
20150
20160
20170
Total102