1. A method of making a data representation of transaction-tax-related information of a transaction, the transaction being represented by a transaction document having transaction-document lines, the transaction-tax-related information having one or more taxation levels, the method comprising: arranging, by a computer, data items representing the transaction-tax-related information according to a data schema for representing transaction-tax related information for different jurisdictions, including jurisdictions with different kinds and numbers of taxation levels; wherein the data schema provides a taxation-line entity for each of the transaction-document lines of the transaction document, wherein the transaction-document lines correspond to respective sub-transactions of the transaction; the data schema provides a taxation-line-item entity, related to the taxation-line entity, for each taxation level of a corresponding transaction-document line, wherein plural taxation-line-item entities are provided for the corresponding transaction-document line associated with plural taxation levels; and wherein an attribute of each taxation-line-item entity is used to indicate the taxation level represented by the taxation-line-item entity.