Financial markets started the year on a bleak note and China remained at the centre of all the trouble. Stocks crumbled around the world, with global equities posting their worst opening day of trading in at least three decades.The big sell-off began in China, triggered by statistics showing slowing manufacturing output throughout Asia. A precipitous 7% fall on the Shanghai stock exchange saw trading suspended for the day.The negative sentiment quickly spread around the world.On the JSE the All-Share Index closed 2.72% lower at 49316.60 and the blue-chip Top 40 Index lost 2.92%.Financials led the South African losses, closing 3.97% weaker. Banks lost 3.52% and property shed 3.18%. Industrials were 2.47% lower. Resources shed 2.14% but the gold index firmed 6.39%.US stocks tumbled to their lowest levels since mid-October, sending the Standard & Poor's 500 Index to its first correction in four years.The S&P 500 fell 2.1% to 2001.26 in early trade, after dropping 0.9% on Thursday to end 2015 with an annual decline for the first time since 2011. The Dow Jones Industrial Average lost 395.59 points to 17029.44. The Nasdaq Composite Index dropped 2.5%.Adding to the turmoil, Saudi Arabia and Bahrain cut ties with Iran over the execution of a dissident cleric, sending Gulf stocks lower and pushing Brent crude higher.Bonds jumped and the yen rallied on demand for haven assets."We've had a number of negatives out there throughout most of last year as investors battled to have a flat year and China is a reminder that there aren't many things to be bullish about going into this year," said Michael O'Rourke of JonesTrading in Connecticut, US.The MSCI All-Country World Index fell 2.3%, topping its slide of 1.5% to start 2001. ..