I would treat it like a ladder although it is again not strictly a ladder. It has the same probability of showing up as a true ladder because once the first digit is known, all other digits are set just like a true descending ladder, so technically it should be valued as such, assuming rarity determines price. Of course a true ladder is more appealing but I would consider this note no less appealing than a 8765432 descending ladder. Just my thoughts as a collector.