@Override
    public String toString() {
        return pf.format(ratioValue());
    }
@Test
    public void testToString() {
        NumberFormat pf = DecimalFormat.getPercentInstance(); //Varies by machine
        pf.setMaximumFractionDigits(3);
        assertEquals(pf.format(0.12345f), MilliPct.ofMilliPct(12345).toString());
        assertEquals(pf.format(-0.12345f), MilliPct.ofMilliPct(-12345).toString());
    }