Actually, an "annuity" is an instrument that releases funds that can be in variable amounts annually, and can be structured to release distributions on any desired time schedule throughout the year. At least that's how they have matured to be (it's just a contract). But I'm sure you're right as to original intent, thus the "annu" in annuity. The term does prompt thoughts of ongoing royalties.

Actually a poor choice of words IMO (misleading), as per my understanding (which is questionable these days) anything designated "annuity" strongly suggests predetermined/known amounts available to be distributed over time.

FWIW,

SGE