Japan was 17th on the list with a score of 7.8 ; the United Kingdom 20th ( 7.6 ) ; and the United States 22nd ( 7.1 ) . Least corrupt countries : Australia , New Zealand and Singapore . Global Perception Index published annually by Survey International . United States ranks No . 1 on the list of 178 nations ; economic rival China at No . 78 . With Somalia at bottom of list : Afghanistan , Myanmar and Iraq .
Least corrupt countries : Australia , New Zealand and Singapore . Global Perception Index published annually by Survey International . United States ranks No . 1 on the list of 178 nations ; economic rival China at No . 78 . With Somalia at bottom of list : Afghanistan , Myanmar and Iraq .