Members of the OECS:
Organization of Eastern Caribbean States
The OECS is a trade agreement of currently 8 countries in Caribbean.
All member states comprise a total area of 3,000 km² and about 0.58 million people. This is 0.00% of the habitable area around the world and 0.01% of the world population. The value of all exported goods of these 8 countries was 2.55 billion US dollars per year at last count.
Official website: https://www.oecs.org/en/