The Shangai Composite Index decreased 19 points or 0.47 percent on Wednesday to close at 3971 points. The decline was led by Sanan Optoelectron (-5.46%), Avic Aviation Engine (-4.57%) and LONGi Green (-3.19%). On the upside, the strongest performers were Yonyou Soft (4.44%), Shaanxi Coal (2.80%) and China Fortune (2.61%).