COVENTRY-based black cab manufacturer Manganese Bronze endured a turbulent day on the markets after revealing an accounting error had caused its losses to widen to more than £4m.The accounting error, blamed on a new computer system, caused the firm to delay publication of its interim results until late on Friday evening leaving no time for it to impact trading.However, investors reacted badly to the announcement yesterday and the firm’s shares plunged in early trading before rallying late on to end the day just 2.3% dow......for the full story register now for free or login below...