DB Depreciation on Calculator

When using the DEPR sheet on TI BAII Plus and I enter DB = 120 and correct info I do not get the correct Depreciation & RBV/RDV - however if I use DB = 160 and the correct info, I get the correct results. Result I am looking for is RBV @ end of Yr 3 = 29,184. I know i can get this by multiplying 57,000(1.2)3

Cost 57,000

Salvage Value @ Purchase = 15,000

Current Fair Value of item = 27,000

Life = 8

DB 20%

Please help