An affluent centre of trade by this point, Timbuktu became part of the Mali Empire in 1324 when it was annexed by Musa I, who is thought to have amassed the equivalent of $415 billion (£327bn) in his lifetime, making him one of the richest, if not the richest person of all time. Musa I commissioned a royal palace in the city, which blossomed under his rule.
In the mid 16th century, Spanish conquistadors began to exploit the vast deposits of the precious metal, sparking an almighty silver rush. Free labourers, conscripted workers and slaves extracted the silver, and the city's elites became incredibly wealthy. Potosí even bagged a mention in Miguel de Cervantes' great novel Don Quixote, where it's described a place of “extraordinary richness”.
Most of the silver was exported in the form of Spanish pieces of eight ('pesos de ocho'). These coins effectively bankrolled Spain's trade economy and fuelled the Chinese trade economy too as European traders used the silver to buy goods from the country. Pieces of eight were even used as early currency in the US, such was their prevalence and prestige.
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Today, Potosí retains many of the buildings from its heyday, but the city has little of the wealth and poverty is commonplace. Though zinc, tin and some silver are still mined, many of the underground facilities are exhausted and unsafe. The city is among the most polluted on Earth and life expectancy is low due to the poor working conditions in the mines.
Back in the 1950s and early 1960s, Detroit was the place to be. The centre of America's buoyant auto industry, the city was booming and its population had swelled to 1.9 million. Swish Neoclassical and Art Deco buildings graced the city, and Detroit had a thriving nightlife and music scene, which was dominated by the world-famous Motown Records and legendary soul singers like Aretha Franklin.
These days, Tehran is rundown and polluted with high levels of deprivation. According to the World Bank, Iranians are 30% poorer in 2018 than they were in the late 1970s, and while the country has massive reserves of oil, the economy is markedly weaker now compared to the days before the revolution.
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In 1999, socialist Hugo Chávez was elected president. His government introduced a series of populist economic policies, which worked at first, helping to raise significant numbers of Venezuelans out of poverty, but they soon became unsustainable. By the end of the Chávez presidency in the early 2010s, inflation had jumped, poverty had actually increased and shortages of basic goods had become widespread.
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Overly reliant on oil, the economy boomed when prices were high in the 2000s, but was devastated by the sharp drop in the price of the commodity in 2014. Venezuela's socialist government failed to diversify during the good times and put all its eggs in one basket. Rigid price controls and a refusal to accept foreign aid have worsened the situation.
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The shortages have only got more severe and hunger is now a fact of life for many people in Venezuela. Crime has spiralled out of control and Caracas has become one of the world's most dangerous cities. No-go areas abound and neighbourhoods that were relatively safe in the 1990s are riddled with crime these days.
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Last year, the Venezuelan economy was 35% smaller than it was in 2013 and GDP per capita had shrunk by a staggering 40%. Shockingly, over the past few years the Venezuelan economy has contracted more than that of the US during the Great Depression and the economy of Russia following the fall of communism. The crisis has left 90% of the population impoverished.
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Unfortunately, things aren't likely to improve in a meaningful way any time soon in Caracas or elsewhere in Venezuela. While the government is planning to refinance its sky-high external debts, confidence that the plan will work out is low and the economy is expected to contract by 18% by the end of 2018 with inflation poised to hit an astonishing 1,000,000%, deepening the economic catastrophe in the country.
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