How far can the APY of $USUAL fall? ( USUAL x)

It was around 1000% at first and started going down, to 900, to 800, to 700 and now it's at 256%.

I started betting when the APY was around 500%.

It was attractive, but now it's halved.

That's all good, but I'm worried about the question:

"How far will it fall"?

Could it be 50%, 10% or 5%?

I know it's variable, but variable also means up, not just down.

What factors cause a variable APY to go up or down?

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