    @Test
	public void calculate_Zero() {

        assertEquals(1, DiscountFactor.calculate(RateAndPeriods.of(0.00,0)).intValueExact());
        assertEquals(1, DiscountFactor.calculate(RateAndPeriods.of(0.00,1)).intValueExact());
        assertEquals(1, DiscountFactor.calculate(RateAndPeriods.of(0.00,10)).intValueExact());
    }