This is a string list of enumerations with an "Other_" literal to support an open enumeration list. Use the "Other_" value in combination with the @OtherType attribute to exchange a literal that is not in the list and is known to your trading partners.
PerEvent
Offer pricing includes one price for all travelers in the party.
PerGroup
Offer pricing is for a group and additional eligibility requirements (such as group size) may apply.