*Excludes Observations that spanned multiple years

Pre 19708
19700
19710
19720
19731
19742
19750
19763
19773
19783
19791
19800
19810
19820
19834
19841
19850
19860
19870
19880
19890
19900
19910
19920
19930
19940
19950
19961
19970
19980
19990
20000
20011
20020
20033
20040
20050
20060
20070
20080
20090
20100
20110
20120
20130
20140
20150
20160
20170
Total31