From the article:

Guyana, a small country in South America, has seen the fastest growth in gross domestic product (GDP) per capita in the world over the past decade.

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A large and sudden expansion in oil production has driven most of this growth. Between 2020 and 2025, the country’s oil production grew 860%, making it a key contributor to global crude oil supply growth.

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It’s too early to see the full effects of this, and hard to measure how far the oil boom has translated into better living standards in the country. Official poverty estimates, for example, have not been published since production began. But there is early evidence of the government channeling oil revenue toward citizens, for instance, through cash grants for every adult, free tuition at public universities, and increasing health spending.