The International Monetary Fund has joined the bears, warning that assets are overvalued and that markets are unusually calm considering how unimpressive the global recovery has been and the risks that we’re facing over the next year. “Valuations in virtually all major asset classes are stretched relative to past norms,” says the IMF report prepared ahead of this weekend’s G20 meeting in Australia. “Long-term bond yields have declined further especially in the euro area but also in the United States and in most emerging economies. Equity valuations have continued to edge higher, as investor sentiment has remained positive despite mixed…