Over - og underkurs på udstedte og købte værdipapirer beregnes og medtages som en del af renteindtægten og amortiseres over værdipapirernes resterende løbetid , enten lineært eller efter den interne rentes ( IR ) metode .
Premiums or discounts arising on issued and purchased securities shall be calculated and presented as part of interest income and shall be amortised over the remaining life of the securities , either according to the straight-line method or the internal rate of return ( IRR ) method . The IRR method shall , however , be mandatory for discount securities with a remaining maturity of more than one year at the time of acquisition .