*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19822
19830
19841
19850
19863
19874
19880
19893
19902
19910
19920
19934
19948
19951
19960
19972
19980
19990
20000
20013
20020
20030
20042
200512
20063
20070
20085
20091
201044
201175
20121
20139
20148
20151
201611
20172
20180
Total207