The value space is integer values from ?768 up to and including 32767.
The lexical space is a finite-length sequence of decimal digits with an optional leading - or +.
<!-- schema -->
<xsd:complexType name="shortlist">
<xsd:sequence>
<xsd:element name="event" minOccurs="0" maxOccurs="unbounded">
<xsd:complexType>
<xsd:complexContent>
<xsd:extension base="xsd:anyType">
<xsd:attribute name="recur" type="xsd:short"/>
</xsd:extension>
</xsd:complexContent>
</xsd:complexType>
</xsd:element>
</xsd:sequence>
</xsd:complexType>
<!-- instance document -->
<event recur="365">A</event>
<event recur="365">B</event>
<event recur="250">C</event>