*Excludes Observations that spanned multiple years

Pre 19706
19700
19716
19722
19731
19740
19751
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19861
19870
19880
19890
19900
19910
19920
19931
19940
19950
19960
19971
19980
19993
20000
20010
20021
20030
20042
20050
20060
20071
20081
20090
20100
20111
20122
20130
20140
20150
20163
20170
Total33