Traders making some of the safest bets on the planet – on tiny price moves in ultra- secure US government debt – were hammered in March as hedge funds scrambled to sell assets to cover losses in other markets.

EMF Financial Products, a New York hedge fund, lost almost $100m of its $406m last month after it plunged 23.2 per cent, according to a letter to investors, although it has rebounded sharply this month.