New Zealand rated number nine last year, with the panel calling it a "silent achiever", but this year it failed to make the top 10.
The United States took the trophy from last year's winner Australia and was praised for its continuing innovation, particularly Nasa's Mars Rover, as well as some positive signs of an economic recovery.
Dr Arif Jubaer, founder of D+, stated "I feel that D+ is making a positive impact on people by reporting positive news. The initiative of the report will encourage individuals and countries to take more positive actions for a positive future."
England, China and Japan rounded out the top five.
Top 10 most positive countries:
1 USA
2 Australia
3 England
4 China
5 Japan
6 Germany
7 Canada
8 France
9 India
10 Sweden