30. St. Vincent and the Grenadines
> Population density: 729.8 people per square mile
> Population: 109,897
> Land area: 151 square miles
> Population growth (1990-2017): 2.2%
The population of this string of 32 islands and cays stretching between St. Lucia and Grenada in the southern Caribbean has changed little since 1990, though the fertility rate has declined noticeably, from 3.10 to 1.99 births per woman. The majority of the population is concentrated in and around Kingstown, the capital.
29. St. Lucia
> Population density: 759.4 people per square mile
> Population: 178,844
> Land area: 236 square miles
> Population growth (1990-2017): 29.4%
Though many decide to leave this southern Caribbean island, mainly to the U.K. and the U.S., St. Lucia’s population continues to grow at the rate of about 1.2% annually. St. Lucia boasts the most Nobel Prize-winners per capita of any country in the world — 1 per 89,422 inhabitants. (They are Derek Walcott for literature and Sir Arthur Lewis for economics.)
28. El Salvador
> Population density: 797.2 people per square mile
> Population: 6,377,853
> Land area: 8,000 square miles
> Population growth (1990-2017): 21.4%
Both the smallest country in Central America and the most densely populated, El Salvador is experiencing a decline in population growth and the gradual aging of its citizenry. About 72% of the total population lives in urban areas, mostly in the capital city of San Salvador.
> Population density: 798.0 people per square mile
> Population: 95,540,800
> Land area: 119,719 square miles
> Population growth (1990-2017): 40.1%
Vietnam’s population is widely dispersed, with the majority living along the Mekong Delta in the south and the Red River Valley in the north. Ho Chi Minh City — the former Saigon — is by far the largest urban area, with a population about eight times as large as that of Hanoi, the capital city.
> Population density: 821.4 people per square mile
> Population: 107,825
> Land area: 131 square miles
> Population growth (1990-2017): 12.0%
Consisting of the island of Grenada and several smaller islands in the Southern Grenadines, this country is a member of The Commonwealth, a voluntary association of independent sovereign states. Many of them — including Canada, India, and Australia, as well as Grenada — were formerly part of the British Empire. About a third of Grenada’s population lives in the capital, St. George’s.