It’s time for central bankers to ask for help. As the International Monetary Fund prepares to downgrade its outlook for the world economy again, monetary policy makers are running low of ammunition to fight a fresh downturn. Bank of America Merrill Lynch calculates they have reduced interest rates more than 600 times since the 2008 collapse of Lehman Brothers Holdings Inc. with the Reserve Bank of India extending the run on Tuesday by cutting its benchmark more than expected. While the European Central Bank and Bank of Japan haven’t ruled out buying even more bonds, there are doubts over how much more quantitative easing can achieve given yields are already around record lows and inflation still remains beneath the target of most policy makers. Even easier monetary policy may just end up propelling asset markets rather than economies. More from Bloomberg.com: Glencore in Freefall as Analysts See Tougher Restructuring That leaves economists and investors increasingly looking toward governments to lead the rescue efforts should the China-led slowdown in emerging markets infect developed nations. BofA Merrill Lynch sees a 25 percent chance of a recession-like slump this year. “Monetary policy is basically exhausted in terms of producing real growth and even inflation,” billionaire Bill Gross of Janus Capital Management LLC told Bloomberg Television this month. “Fiscal... More