*Excludes Observations that spanned multiple years

Pre 19701
19700
19711
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19843
19850
19861
19871
19881
19890
19903
19912
19920
19934
19942
19956
19960
19970
19984
19993
20001
20010
20021
20030
20042
20050
20060
20071
200829
20099
20100
20111
20120
20132
20140
20150
20161
20170
20180
20190
20201
20217
20223
20233
20240
Total93