BBC: Can Denmark succeed where Switzerland failed?

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However, a positive side effect for borrowers of the negative interest rate is that for the first time, a Danish lender, Nordea Kredit, is reportedly paying mortgage holders to borrow money by charging a negative interest rate. But others are not following suit as it's unclear how to handle a negative interest rate.

Indeed, there are calls now in Europe to fashion IT systems and discuss how to manage negative interest rates. There's an estimated $4 trillion of sovereign debt, including even 10-year Swiss bonds, which have negative yields.
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