*Excludes Observations that spanned multiple years

Pre 197063
19700
19710
19721
19731
19741
19750
19760
19773
19782
19791
19800
19812
19823
19830
19841
19850
19860
19870
19880
19895
19900
19911
19920
19930
19941
19951
19963
19971
19980
19990
20001
20010
20021
20033
20041
20052
200610
20070
20084
200913
20106
201116
201215
20135
20141
20157
20163
20172
Total180