Slowing China economy may not yet have hit bottom

China is set to reveal its weakest quarter of annual growth in nearly three years on Friday, with investors fretting the economy could cool even further in coming months and further dampen global growth.

Economists polled by Reuters expect China delivered a fifth successive quarter of slowing annual growth in the first three months of 2012 of 8.3 percent, leaving the economy on track for its weakest full year of expansion in a decade.

The forecast is a whisker above the 8.1 percent posted in the second quarter of 2009, when policymakers in the world’s second-biggest economy were rolling out 4 trillion yuan ($635 billion) of stimulus to escape the grip of a financial crisis that had driven global trade – to which China’s growth is levered – to a virtual halt.

“Underlying economic indicators are more volatile and mixed than before, suggesting structural changes may be adding mist to…