/// <summary>
 /// Sets a range value
 /// </summary>
 /// <param name="range"></param>
 public void SetRangeValue(Range range)
 {
     this.range     = range;
     this.valueType = PivotColumnValueType.Range;
 }
 /// <summary>
 /// Sets a scalar value
 /// </summary>
 /// <param name="val">A value which matches PivotColumn's data type</param>
 public void SetScalarValue(object val)
 {
     this.val       = val;
     this.valueType = PivotColumnValueType.Scalar;
 }