Read the full story on the FT.com: http://on.ft.com/1nv7Z8t<br /><br />► Subscribe to the Financial Times on YouTube: http://bit.ly/FTimeSubs<br /><br />Since devaluing the renminbi last summer, the People's Bank of China has found it increasingly difficult to control the value of its currency, with knock-on effects on global equity markets. Patrick McGee explains.<br /><br />For more video content from the Financial Times, visit http://www.FT.com/video<br /><br /><br />Twitter https://twitter.com/ftvideo<br />Facebook https://www.facebook.com/financialtimes
