@Override
    public Num getValue(int index) {
        return averageTrueRangeIndicator.getValue(index);
    }
@Test
    public void testXls() throws Exception {
        BarSeries xlsSeries = xls.getSeries();
        Indicator<Num> indicator;

        indicator = getIndicator(xlsSeries, 1);
        assertIndicatorEquals(xls.getIndicator(1), indicator);
        assertEquals(4.8, indicator.getValue(indicator.getBarSeries().getEndIndex()).doubleValue(),
                TestUtils.GENERAL_OFFSET);

        indicator = getIndicator(xlsSeries, 3);
        assertIndicatorEquals(xls.getIndicator(3), indicator);
        assertEquals(7.4225, indicator.getValue(indicator.getBarSeries().getEndIndex()).doubleValue(),
                TestUtils.GENERAL_OFFSET);

        indicator = getIndicator(xlsSeries, 13);
        assertIndicatorEquals(xls.getIndicator(13), indicator);
        assertEquals(8.8082, indicator.getValue(indicator.getBarSeries().getEndIndex()).doubleValue(),
                TestUtils.GENERAL_OFFSET);
    }