Investment bank UBS has broken down a number of different indicators to show how well-off different parts of the world are, in a fantastic update on world prices and wages sent out to clients on Tuesday.
One of those indicators is particularly simple — how much it costs to buy an iPhone 6, a Big Mac, a kilo of bread or a kilo of rice.
The authors of the research explain: "As staple consumer goods, the McDonald’s Big Mac and the Apple iPhone will be the same quality and nature whether bought in Doha or Rio de Janeiro. This makes their worldwide prices and affordability comparable."
The range spreads from Zurich, where buying an iPhone 6 takes on average less than three days of work, to Nairobi, where it takes months of labour to access precisely the same product.