The following are the biggest percentage decliners on the TSX Venture Exchange in mid afternoon trading with their price movements NORTHERN VERTEX MINING (NEE.V), $0.17, 0.08, 32.00% MALBEX RESOURCES (MBG.V), $0.28, 0.12, 29.11% PETRO RIO (PRJ.V), $0.18, 0.05, 23.40%