Applies mainly to convertible securities. Interest that has accumulated between the most recent payment and the sale of a bond or other fixed-income security. At the time of sale, the buyer pays the seller the bond's price plus "accrued interest," calculated by multiplying the coupon rate by the fraction of the coupon period that has elapsed since the last payment. (If a bondholder receives $40 in coupon payments per bond semiannually and sells the bond one-quarter of the way into the coupon period, the buyer pays the seller $10 as the latter's proportion of interest earned.)