*Excludes Observations that spanned multiple years

Pre 19701
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19841
19850
19860
19870
19881
19890
19902
19910
19923
19931
19944
19954
19962
19970
19982
19990
20001
20010
20020
20031
20040
20052
20060
20071
20080
20092
20106
20113
20120
20130
20140
20150
20160
20170
Total37