Market discount is the difference between the purchase price of a bond and its stated redemption price at maturity. (investinginbonds.com)
«Market discount» arises when a bond is purchased on the secondary market for a price that is less than its stated redemption price by more than a statutory amount. (fidelity.com)
The ~ 22 % increase in redemption price for first class still isn't horrible to me. (uponarriving.com)