BEIJING: China's manufacturing activity unexpectedly contracted in January, an official factory survey showed on Monday (Jan 27), its weakest since August, keeping alive calls for stimulus in the world's second-largest economy. The official purchasing managers' index (PMI) contracted to 49.1 in January from 50.1 in December, below the 50-mark separating growth from contraction and missing a median forecast of 50.1 in a Reuters poll. China's US$18 trillion economy hit the government's growth