*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19862
19871
198814
19890
19903
19913
19920
19934
19945
19957
19962
19976
19982
19993
20001
20014
20020
20030
20041
20052
20061
20071
20080
20090
20100
20110
20120
20130
20140
20150
20160
20170
Total62