*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19721
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19849
19856
19865
198722
198817
198914
19906
199119
19924
19931
19941
19951
19962
19973
19983
199919
200037
200134
20026
20035
20040
20059
20065
20074
20081
20098
20106
20115
20129
20138
20142
20158
201610
20174
20180
Total294