%age increase backtest

Hi

Like this (BUY – CROSSOVER(EMA(CLOSE,13),EMA(CLOSE,34))) and SELL – CROSSOVER(EMA(CLOSE,34),EMA(CLOSE,13)))…will it be possible to backtest (in Pi) a thing like BUY when open price reaches 1.75% or sell when open price reaches -1.60%…what I mean is instead of going by the conventional way can it be coded %age increase, decrease wise ?

Not any averages only percentage of a price at start.

Thanks