*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19731
19740
19750
19760
19770
19781
19790
19800
19810
19821
19830
19840
19855
19863
19876
198812
19891
19908
19911
19922
19930
19942
19950
19961
19970
19983
19991
200012
20012
20020
20031
20040
20050
20060
20070
20081
20090
20102
20113
20121
20130
20143
20151
20165
20170
20180
Total79