World markets in decline, led by 6% slump in China

World markets are falling again, led by a 6% slump in Chinese shares. Investors seem spooked by more weak data, and oil falling below $30 a barrel once again. Stock markets in London, Frankfurt and Paris followed suit, with a bumpy start to trading, and falls off 1.5 to 1.8%. Global markets had slightly rebounded after falling dramatically last week. Meanwhile, all eyes will be on a U.S. Federal Reserve meeting this week to see whether it acknowledges concerns over China and whether that will delay any interest rate increases this year.