<xs:attribute name="Type" use="optional">
    <xs:annotation>
        <xs:documentation xml:lang="en">Specifies the type of amount being sent.</xs:documentation>
    </xs:annotation>
    <xs:simpleType>
        <xs:restriction base="xs:NMTOKEN">
            <xs:enumeration value="Amount">
                <xs:annotation>
                    <xs:documentation xml:lang="en">The discount is an amount.</xs:documentation>
                </xs:annotation>
            </xs:enumeration>
            <xs:enumeration value="Percent">
                <xs:annotation>
                    <xs:documentation xml:lang="en">The discount is a percentage.</xs:documentation>
                </xs:annotation>
            </xs:enumeration>
            <xs:enumeration value="PlusUpAmount">
                <xs:annotation>
                    <xs:documentation xml:lang="en">A discount on an international fare that is not a stored fare.</xs:documentation>
                </xs:annotation>
            </xs:enumeration>
        </xs:restriction>
    </xs:simpleType>
</xs:attribute>