The world's most expensive city for expats

This city is the most expensive for expats

In the world's most expensive city for expatriates, a fast food meal will set you back over $17, a pair of jeans will leave you out of pocket by $250 and a non-descript apartment costs a whopping $6,800 a month.

So where is this place where the streets must be paved with gold? It's the city of Luanda, the capital of oil-rich Angola, which has once again topped human resource consultancy Mercer's 2015 Cost of Living ranking released on Wednesday.

The African seaport has held the title of the world's priciest city every year since 2010, except for 2012, when it was briefly knocked off the top spot by Tokyo.

"Despite being recognized as a relatively inexpensive city, the cost of imported goods and safe living conditions in this country are available at a steep price," said Mercer of Luanda, which typically attracts expatriates that work for multinationals operating in the energy or diamond sectors.

African, Asian, and European cities dominated the top 10 most expensive locations for employees working abroad.

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Hong Kong follows Luanda as the second most expensive city, a reflection of the relative resilience of its local currency, the Hong Kong dollar, which is pegged to the greenback.

Zurich, Singapore and Geneva ranked third, fourth and fifth respectively. Rounding out the top 10 were Shanghai, Beijing, Seoul, Bern and N'Djamena, the capital of Chad.

Mercer's survey ranks 207 cities across five continents and compares the cost of over 200 items in each location, including housing, transport, food, clothing, household goods, and entertainment in U.S. dollar terms. It is used to help multinational companies and governments determine compensation allowances for their expat employees.

This year's survey found instability in housing markets and inflation for goods and services were among the biggest swing factors in the cost of doing business in a global environment.

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The $6,800 monthly cost of renting a two-bedroom unfurnished apartment "of international standards in an appropriate neighborhood" in Luanda compared to $5,500 in New York and $4,899 in London – the world's financial capitals, which placed 16th and 12th in the rankings respectively.

European cities slide down; U.S. cities climb up

While Europe featured prominently in the top 10, many Western European cities in fact dropped in rankings due to the euro's weakening against the U.S. dollar. Paris and Milan, for example, slipped 19 and 23 spots down the ranking to 46th and 53rd place.

"European currencies have weakened against the U.S. dollar which pushed most Western European cities down in the ranking," Mercer said. "Additionally, other factors like the euro zone's economy, falling interest rates, and increasing unemployment have impacted these cities."

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The opposite was the case for American cities, which climbed dramatically in the rankings, reflecting the greenback's swift appreciation.

While New York, the highest-ranked U.S. city, remained stable in the rankings this year, cities on the West Coast, including Los Angeles and Seattle climbed 26 and 47 places respectively, to the 36th and 106th spots. Portland and Winston-Salem were the least expensive cities in the U.S. surveyed for expatriates, ranking in 135th and 157th place.