Story highlights The World Generosity Index 2016 says giving is increasing worldwide

Only five of the G20 nations appeared in the index's top 20

(CNN) When it comes to generosity, few countries can match Myanmar.

For the third year in a row, Myanmar topped the Charities Aid Foundation World Giving Index which averages out the percentage of people in each country who donated money, volunteered or helped a stranger in the previous month.

The Southeast Asia nation again topped the United States, which was No. 2 for the second straight year. In 2014, the two countries shared top honors.

According to its research, 91% of Myanmar residents gave money to charity in the past year, 62% said they had helped a stranger, and 55% claimed they had volunteered.

"It's important to remember that our Index measures countries by the proportion of the population giving -- not how much they give," CAF Media Director Simon Ward told CNN. Myanmar's population of about 56 million is less than one-fifth that of the US.

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