*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
19870
19881
19890
19900
19914
19920
19930
19941
19952
19960
19970
19980
19990
20000
20010
20021
20030
20040
20050
20063
20070
200811
20090
201029
201125
20120
20131
20140
20150
20160
20170
Total80