*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19853
19860
19875
198817
19891
19909
19913
199211
19931
19949
19954
19960
19976
19989
19992
20005
20011
20020
20030
20042
20053
20061
20072
20081
20090
20100
20110
20120
20130
20140
20150
20160
20170
Total95