@Override
 public Integer getStartShift() {
   // return Math.max(20, getDaysSpan());
   return Math.max(chaikinOscillator.getStartShift(), sma.getStartShift()) + getDaysSpan();
 }
 @Override
 public Integer getOutputBeginIdx() {
   return Math.max(chaikinOscillator.getOutBegIdx().value, sma.getOutBegIdx().value)
       + getDaysSpan();
 }
 @Override
 protected Boolean isInDataRange(TalibIndicator indicator, Integer indicatorIndex) {
   return (getDaysSpan() < indicatorIndex)
       && (indicatorIndex < chaikinOscillator.getChaikinOsc().length);
 }