*Excludes Observations that spanned multiple years

Pre 197014
19700
19711
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19871
19880
19890
19900
19910
19921
19933
19945
19959
199610
199713
199813
19996
20001
20014
20023
20038
20043
20052
20065
20074
20081
20094
20105
20117
20124
20131
20144
20152
20162
20174
Total140