*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19876
19880
19890
19900
19915
19920
19931
19941
19952
19960
19977
19980
19990
20000
20011
20020
20030
20041
20051
20060
20070
20080
20090
201019
201120
20120
20131
20141
20150
20160
20170
Total66