seq 

if no "total" attribute exist then this attribute can be used to number the data elements like a count, this enables the receipt end to determine if any data clusters were lost.

Attribute Information

Used By

Element tml:data

Source 

<xs:attribute name="seq" type="xs:integer" use="optional">
  <xs:annotation>
    <xs:documentation>if no "total" attribute exist then this attribute can be used to number the data elements like a count, this enables the receipt end to determine if any data clusters were lost.</xs:documentation>
  </xs:annotation>
</xs:attribute>

Sample