*Excludes Observations that spanned multiple years

Pre 19709
19700
19711
19721
19730
19740
19750
19766
19771
19781
19790
19800
19810
19820
19830
19840
19850
19861
19870
19880
19890
19901
19910
19920
19931
19940
19951
19960
19971
19980
19991
20000
20010
20020
20030
20040
20050
20060
20070
20080
20090
20100
20110
20120
20130
20140
20150
20160
20170
Total25