*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19751
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19890
19901
19910
19921
19931
19941
19950
19964
199711
199817
199912
20007
20012
20025
20031
20045
20050
20062
20075
20083
20090
20101
20112
20120
20130
20140
20150
20163
20170
Total85