*Excludes Observations that spanned multiple years

Pre 197056
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19890
19900
19910
19920
19930
19940
19950
19960
19970
19980
19990
20000
20011
20021
20030
20040
200529
200613
20076
200817
20095
20103
20117
20120
20130
20140
20150
20160
20170
Total138