*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19781
19790
19801
19811
19820
19831
19840
19850
19862
19871
198820
19894
199011
199116
19925
199315
199422
199510
199613
199719
19983
19991
20001
20013
20022
20030
20040
20054
20061
20071
20083
20090
20101
20114
20120
20130
20140
20150
20160
20170
Total166