*Excludes Observations that spanned multiple years

Pre 19708
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19841
19850
19860
19870
19880
19896
19900
19910
19922
19936
19941
19953
19960
19973
19980
19995
20000
20010
20020
20031
20041
20050
20060
20070
20080
20090
20100
20110
20121
20130
20140
20150
20160
20170
Total38