Central banks in the developing world have lost $81bn of emergency reserves through capital outflows and currency market interventions since early May, even before renewed turmoil in emerging markets.

The figure, excluding China, is equal to roughly 2 per cent of all developing country central bank reserves, according to Morgan Stanley analysts, who compiled the data from central bank filings for May, June and July.

Some countries have suffered more precipitous drops. Indonesia has lost 13.6 per cent of its central bank reserves from the end of April until the end of July, Turkey has spent 12.7 per cent and Ukraine has burnt through almost 10 per cent. India, another country that has seen its currency pummelled in recent months, has shed almost 5.5 per cent of its reserves.