These three sources all say that the bond roll-down effect is negative if the bond is trading at a premium:
- https://www.investopedia.com/terms/r/rolldownreturn.asp
- https://corporatefinanceinstitute.com/resources/fixed-income/rolling-down-the-yield-curve/
- https://www.wallstreetoasis.com/resources/skills/finance/rolling-down-the-yield-curve
It seems to me this is mixing up roll-down and pull-to-par. As long as the yield curve is not inverted (i.e. is upward sloping to the right), then as time passes, the yield of the bond decreases. Doesn't that mean that roll-down (isolated from the pull-to-par effect) has a positive effect on bond price, regardless of whether the bond is at a premium or discount?
If a premium bond's price is declining over time with no change to the yield curve, couldn't that simply mean that the pull-to-par effect (negative) is stronger than the roll-down effect (positive)?
And, if the yield curve is steep enough, couldn't that make the roll-down stronger than pull-to-par, meaning that a premium bond's price could increase?
Or, since all three sources above agree, maybe I'm just missing something important. What is it?
Quote from the first source above:
Roll-down return works in two ways. The direction depends on whether the bond is trading at a premium or at a discount to its face value.
If the bond is trading at a discount, the roll-down effect will be positive. This means the roll-down will pull the price up towards par. If the bond is trading at a premium the opposite will occur. The roll-down return will be negative and pull the price of the bond down back to par.
Thanks. This is my first question in this community.