*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
19880
19890
19900
19910
19921
19931
19943
19951
19960
19970
19980
19993
20000
20012
20020
20032
20040
20051
20060
20070
20087
20090
201042
201137
20121
20132
20140
20150
20160
20170
Total105