Chinese stocks plunged rapidly out of the Wednesday open, with the Shanghai Composite Index SHCOMP, -5.90% starting down 7% and extending the loss to 8.2%, before recovering slightly to 4.8%. The selloff came despite a rare pledge by the People’s Bank of China as the markets opened that it would closely watch stock movements and continue to use multiple ways to support the state-backed margin-finance entity — China Securities Finance Corp. (CSF) — in order to safeguard the stability of the markets and “hold the line against systemic and regional financial risks.” MORE