I have not taken Geodon myself. I did watch my H go through it. He'd needed some klonopin to help him through.
I totally agree with still_crazy's suggestion of keeping the taper at 10% (or below) each time the taper drops (or is calculated).
Too often, the dose %, set for each decrease is far too high, some as high as 50% and higher.
I wish you the very best as you taper off of Geodon.