Bloomberg writes that investors who fret about when and how global central banks will run down their crisis-era balance sheets can be relaxed about the biggest of them all -- China's. Whereas the Federal Reserve's $4.5 trillion asset pile is set to be shrunk and the European Central Bank's should stop growing by the end of this year as the outlook brightens, China's $5 trillion hoard is here to stay for the time being -- and could even still expand, according to the majority of respondents in a Bloomberg survey of People's Bank of China watchers. The PBOC balance sheet is a fundamentally different beast from its global peers -- run up through years of capital inflows and trade surpluses rather than hoovering up government bonds -- but it still matters for the global economy. Changes in the amount of base money in the world's largest trading nation are having a bigger impact than ever, making the variable key for stability in a year when political transition in Beijing is in the cards. "China is more than a couple of years away from balance-sheet contraction," said Ding Shuang, chief China economist at Standard Chartered Plc in Hong Kong, pointing out that the growth in the broad money supply is still behind the government's target.