*Excludes Observations that spanned multiple years

Pre 19700
19700
19711
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19841
198512
198625
198746
198844
198942
199054
199141
19924
199319
19947
199521
19962
19974
19981
199915
200017
20016
20022
20030
20040
20053
20061
20071
20081
20090
20100
20110
20121
20130
20142
20155
20166
201718
20181
20190
20200
Total403