<xs:attribute name="areaUnits" default="squareFoot">
    <xs:annotation>
        <xs:documentation>
				Area measurement units
			</xs:documentation>
        <xs:appinfo>
				squareFoot
			</xs:appinfo>
    </xs:annotation>
    <xs:simpleType>
        <xs:restriction base="xs:token">
            <xs:enumeration value="squareFoot" />
            <xs:enumeration value="squareYard" />
            <xs:enumeration value="acre" />
            <xs:enumeration value="squareCentimeter" />
            <xs:enumeration value="squareMeter" />
            <xs:enumeration value="hectare" />
            <xs:enumeration value="unknown" />
        </xs:restriction>
    </xs:simpleType>
</xs:attribute>