XML Tutorial/XML Schema/gYear
The gYear datatype represents a Gregorian year
<!-- schema -->
<xsd:element name="interval">
<xsd:simpleType>
<xsd:restriction base="xsd:gYear">
<xsd:minInclusive value="1776"/>
<xsd:maxInclusive value="1976"/>
</xsd:restriction>
</xsd:simpleType>
</xsd:element>
<!-- instance document -->
<interval>1842</interval>