Returns the number that this should round the default values to.
        
        :return     <int>

def roundTo(self):
        """
        Returns the number that this should round the default values to.
        
        :return     <int>
        """
        if self._roundTo is None:
            min_val = max(self.minimum(), 1)
            max_val = max(self.maximum(), 1)
            max_labels = self.maximumLabelCount()
            
            return int(round((max_val - min_val) / float(max_labels)))
            
        return self._roundTo