NEW YORK ( ETF Expert) -- The familiar pattern of May-June gloom for stocks only led to a 5% selloff in 2013. Bonds, however, witnessed a repricing that many had not seen since 1994. Intermediate-term Treasuries lost 7% to 8%. Munis fell more than 10%. Meanwhile, investors trampled emerging market bonds for 12% to14%.Why did people redeem assets from bond funds so quickly? Why did the pace of those redemptions create liquidity issues for the fixed-income marketplace? In brief, the Federal Reserve had hinted that it might slow down the rate of its quantitative easing experiment of buying bonds to push rates lower. Consequently, the 10-year yield nearly doubles from 1.6% to 3% in an extremely short time frame. Many are now suggesting that a future crash in bond funds is a near certainty. They maintain that when rates rise -- not if they rise -- bond mutual funds and bond ETFs will not be able to handle the selling due to a lack of liquidity in the underlying assets. Indeed, during the height of this year's chaos, municipal bond ETFs like PowerShares National Muni ( PZA) and iShares S&P National Muni ( MUB) were trading at net asset value discounts of 300 basis points for at least a week. In the world of exchange-traded investing, premiums and discounts are supposed to be negligible.