Fragile Five: Have the members changed?

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The emerging markets most at risk to the U.S. Federal Reserve's forthcoming rate hike will be different from those that suffered from last year's "taper tantrum", according to experts at Citigroup.

"Last year's easy distinction between 'deficit' and 'surplus' countries is morphing into a distinction between 'commodity exporters' and 'manufactured goods exporters,'"Citi strategists led by Guillermo Mondino wrote in a note.

Brazil, Indonesia, India, Turkey and South Africa – dubbed the Fragile Five - were at the center of an emerging markets storm last summer triggered by concerns over the U.S. central bank turning off the liquidity taps - a situation made worse by nervousness about China's growth outlook.

These five countries all had large current account deficits, which made them vulnerable to a withdrawal of foreign capital in an environment of tighter liquidity.

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A year later, countries such as India and Turkey, both manufactured goods exporters, have staged decisive current account adjustments while commodity exporters including Brazil and South Africa have even larger deficits.

Looking ahead to Fed rate rise, which some analysts forecast for early next year, commodities exporters are likely to see deteriorating terms of trade, worse export performance, wider current account deficits, further currency depreciation and bigger inflation problems, Mondino said.

The environment for commodities exporters will remain tough as demand out of China slows and Fed tightening fuels strength in the U.S. dollar, Citi said. A stronger dollar is negative for commodities demand as it means products are less affordable for those using other currencies.

"If investors build up a strong enough sense that commodity-exporting economies have higher levels of macro vulnerability then capital flight from these markets will continue to pressure nominal exchange rates and, hence,continue to create challenges for central bankers," Mondino said.

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Commodities-focused emerging market currencies have come under notable pressure in the past month, with the South African rand and Brazilian real falling 5.6 percent and 8.2 percent respectively against the U.S. dollar. By comparison, the Indian rupee and Turkish lira have declined 1. 5 percent and 4.8 percent respectively over the same period.

While commodity exporters with deficits are the most vulnerable group of countries in a risk-averse environment, Citi says commodity exporters with current account surpluses including Russia and Nigeria are also at risk.

"Even if commodity producers have differing levels of external vulnerability – some have surpluses, some have deficits – they all seem to share a common growth problem," he said.

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Is there still a Fragile Five?

Mark Matthews, head of research, Asia at Bank Julius Baer agrees the Fragile Five club may not be as relevant this time around.

Last May, on top of current account deficit concerns, all five countries were awaiting major elections.

Four out of five countries have since gone through elections, which in some cases has altered their economic outlooks, he noted.

"Take India for example. It shouldn't be in the grouping," Matthews said.

"In any case, I don't think there will be a panic reaction in emerging markets. But if there is, there will be differentiation just like there was last year where some markets were totally unfazed," he added.