*Excludes Observations that spanned multiple years

Pre 19701
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19831
19841
19850
19860
19870
19880
19890
19900
19910
19920
19931
19946
199513
19960
19973
19980
19990
20000
20010
20025
20031
20040
20050
20060
20070
20081
20090
20100
20110
20120
20130
20140
20150
20160
20170
Total33