public BigDecimal interQuartileMean_as_BigDecimal() {
		BigDecimal mean = BigDecimal.ZERO;
		switch (type) {
		case 1:
		case 12:
			BigDecimal[] bd = this.getArray_as_BigDecimal();
			mean = Stat.interQuartileMean(bd);
			bd = null;
			break;
		case 14:
			throw new IllegalArgumentException("Complex interquartile mean is not supported");
		default:
			throw new IllegalArgumentException("This type number, " + type + ", should not be possible here!!!!");
		}
		return mean;
	}