def METHOD_NAME(self):
    result = {}
    # use Decimal to avoid rounding errors
    x = decimal.Decimal(0)
    width = decimal.Decimal(self._width)
    width_exponent = -width.as_tuple().exponent
    with self._lock:
        if self._count > 0:
            for y in self._quartiles:
                yp = int(y * 100 / self._count)
                if yp != 0:
                    result[round(float(x), width_exponent)] = yp
                x += width
    return result