XML Tutorial/XML Schema/year

The day and month are not known, and so it makes sense to have an element that only requires the year

   <source lang="xml">

<?xml version="1.0"?> <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"

 targetNamespace="http://www.wbex.ru" xmlns="http://www.wbex.ru"
 elementFormDefault="qualified">
 
 <xs:element name="last_seen" type="xs:year" />

</xs:schema>

File: Data.xml <?xml version="1.0"?> <last_seen>1950</last_seen></source>