*Excludes Observations that spanned multiple years

Pre 19701
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19861
19871
19881
19891
19902
19911
19921
19930
19940
19950
19961
19971
19980
19990
20000
20010
20021
20031
20040
20050
20060
20070
20080
20090
20100
20111
20120
20130
20140
20150
20160
20170
Total14