As stock markets climb around the world, Chinese traders aren’t celebrating.

China’s export sales contracted 15% in March, a shock outcome that deepens concern about sputtering Chinese economic growth.

China’s exports gained steam in May thanks to firmer global demand, but an unexpected fall in imports signalled weaker domestic demand that could continue to weigh on the world’s second-largest economy.

China’s factory growth held at an 18-month high in November on firm domestic and foreign demand, defying expectations the economy faces a modest slowdown as 2013 draws to a close.