When market rates of interest rise after a fixed-rate security is purchased th

When market rates of interest rise after a fixed-rate security is purchased the value of the now-below-market fixed-interest payments declines so the
market value of the investment falls. On the other hand if market rates of interest fall after a fixed-rate security is purchased the fixed-interest
payments become relatively attractive and the market value of the investment rises. Assuming these price changes are not viewed as giving rise to an
other-than-temporary impairment how are they reflected in the investment account for a security classified as held-to-maturity?