The yen strengthened and the pound was sold off as investors unwind their carry trades -- where money is borrowed in low-yielding countries to be invested in economies with higher returns. Although the yen was weaker this morning after robust US data on Friday, investors are worried about the level of risk in the global economy, particularly after the Chinese trade surplus came in above expectations. Exports for February totaled 82.1 bln usd, up a stunning 51.7 pct year-on-year. "Strong Chinese exports suggest the economy isn't cooling off there and have sparked fears that the (Chinese) government might try to curb future investments to keep growth in check," said Hans Redeker at BNP Paribas. Redeker noted this would weigh on commodity prices, raising risk in the global economy and making carry trades more expensive. Investors are worried that this sort of domino-effect should spiral out of control. The yen is sold mostly in carry trades, so it has gained the most from the unwinding of these trades. The pound and Australian and New Zealand dollars were hurt the most as they have been traditionally bought in search of higher yields. The euro also rose against the dollar as confidence in the US economy remains shaky. "The dollar is also under selling pressure as the jobs data on Friday is not as strong as the headline figure suggested," as a fall in unemployment in February was caused by a fall in the participation rate, according to Redeker, who noted jobs growth may even turn to negative in coming months.