<xsd:group name="TradingEventsBase.model"> <xsd:annotation> <xsd:documentation xml:lang="en">Choice between a trade and a post-trade event.</xsd:documentation> </xsd:annotation> <xsd:choice> <xsd:sequence> <xsd:element name="originatingEvent" type="OriginatingEvent" minOccurs="0" /> <xsd:element name="trade" type="Trade" /> </xsd:sequence> </xsd:choice> </xsd:group>