The main variables that make up the Parabolic SAR are Step and Maxmum Step. Wilder suggests keeping the values at 0.02 and 0.20. Parabolic SAR performs best in trending markets
The higher the value of the step, higher is the sensitivity of the indicator with respect to price change, but that does not mean that a very high step is desirable. When it is too high, the indicator is too volatile and this limits its usefulness. The Maximum Step is used for adjusting the SAR as price moves. The lower the Maximum Step, the higher the distance to the trailing stop from the price.