*Excludes Observations that spanned multiple years

Pre 19706
19700
19710
19720
19730
19740
19750
19760
19771
19780
19790
19801
19810
19821
19830
19842
19850
19860
19870
19880
19890
19900
19915
19923
19931
19941
19951
19960
19970
19980
19990
20002
20010
20021
20030
20040
20050
20061
20070
20080
20090
20100
20110
20120
20130
20140
20150
20160
20170
20180
Total26