*Excludes Observations that spanned multiple years

Pre 197014
19700
19710
19720
19730
19741
19750
19760
19770
19781
19790
19800
19810
19820
19830
19840
19850
19861
19870
19880
19890
19900
19910
19920
19930
19940
19952
19960
19970
19980
19990
20000
20010
20020
20030
20040
20050
20060
20070
20080
20094
20102
20113
20120
20130
20140
20150
20160
20170
Total28