*Excludes Observations that spanned multiple years

Pre 197014
19700
19710
19720
19732
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19841
19851
19860
19870
19880
19890
19900
19910
19920
19932
19942
19954
19961
19972
19982
19997
200010
20012
20022
20031
20042
20051
20060
20070
20081
20091
20102
20111
20127
20133
20143
20152
20166
20171
Total83