Members of the USAN:
Union of South American Nations

The USAN is an alliance of states of currently 12 countries in South America.

All member states comprise a total area of 17.71 million km² and about 434.15 million people. This is 11.7% of the habitable area around the world and 5.5% of the world population. With an economic output of 3,210.26 billion US dollars annually, they represent around 3.3 percent of the global economy. The value of all exported goods of these 12 countries was 708.43 billion US dollars per year at last count.

Official website (Spanish):
Map of member countries: USAN - Union of South American Nations
Argentina45.81 M2,780,000 km²
Bolivia11.83 M1,099,000 km²
Brazil213.99 M8,516,000 km²
Chile19.21 M757,000 km²
Colombia51.27 M1,142,000 km²
Ecuador17.89 M256,000 km²
Guyana0.79 M215,000 km²
Paraguay7.22 M407,000 km²
Peru33.36 M1,285,000 km²
Suriname0.59 M164,000 km²
Uruguay3.49 M176,000 km²
Venezuela28.70 M912,000 km²