protected static double convertPercentileToX(double percentileLevelIteratedTo){
  double x=1 / (1.0D - (percentileLevelIteratedTo / 100.0D));
  return Math.log10(x);
}

protected static double convertPercentileToX ( double percentileLevelIteratedTo ) { double x = 1 / ( 1.0D - ( percentileLevelIteratedTo / 100.0D ) ) ; return Math . log10 ( x ) ; }
x = 1 / ( 1 - percentage )
