D. Further possibilities in multi - country data exchanges
10.23. Possibilities of multi-country exchanges and use of mirror data. A trading partner can agree not to compile export information but rather to replace it with the import information compiled by the other, as the information on imports is considered more reliable (see para.9.49 on United States of America-Canada data exchange ). A country could also refrain entirely from compiling export and import information for a trading partner and adopt instead the partner’s export and import data as representing those for its imports and exports with that trading partner, if this approach would provide the best available data. Many further variations of mutually beneficial data exchanges and use of mirror data could be developed and implemented. However, careful consideration needs to be given to whether such data exchanges constitute best or desirable practices, as the differences in mirror statistics are a major quality concern (see chap. IX, sect. C). One particular concern in the case of multi country data exchanges is the risk of double counting.
10.24. Data exchanges between members of a customs union. In the case of a customs union, additional possibilities of multi - country data exchanges exist and could be used in the future. For example, the implementation of a centralized customs clearance for extra-union trade within the European Union requires the systematic data exchange between countries since all member States' customs administrations act as one administration within a single market. Regarding intra-union trade, it could be envisaged that the required information would be partially (i.e., for specific commodities such as oil and gas) or entirely compiled centrally on the union level and not on the country level.
10.25. Example of the European Union: single authorization (SA), single authorization for simplified procedures (SASP) and centralized customs clearance (CCC). Single Authorization is an actually applied customs scheme, in which an authorization is granted by customs in one member State (the Supervising member State) permitting in all participating member States the use of customs procedures with economic impact (CPEI). Where an authorization covers the use of the simplified declaration procedure (SDP) or the local clearance procedure (LCP), it is referred to as an SASP. Such an authorization is a trade facilitation measure which allows an economic operator to conduct his customs business from the member State where he is established, irrespective of the member State in which the goods are located at the time of their release. It is expected that a wider use of the SASP will pave the way for the implementation of centralized customs clearance (CCC), a future standard procedure under the EU Customs Code. Centralized customs clearance will systematically allow economic operators to centralize and integrate accounting, logistics and distribution functions with consequent savings in administrative and transaction costs, thus providing a genuine simplification.
10.26. Implications for trade statistics. The single authorization for simplified procedure and the future centralized customs clearance make it necessary to redefine the terms “importing member State” and “exporting member State” for statistical purposes because the place where the customs declarations is available is disassociated from the location of the goods. Neither the supervising member State nor the participating member State are a priori a suitable territory for to allocating imports or export in statistics. Only the concepts of “member State of destination” for imports and “member State of actual export” enable the allocation of trade to be more closely connected to the economic impact on a member State, with a better use for balance-of-payments and national accounts. Since the customs declaration as source of information on imports and exports is lodged in another member State, the compiling member State has to either collect information directly from economic operators (as is done actually under the single authorization for simplified procedure for national purposes) or receive information from the member State where the customs declaration was lodged (as is expected to be the case for centralized customs clearance when the mutual exchange of information has been implemented).
 The term “customs procedure with economic impact” is defined in the EU Customs Code and is understood as applying to the following arrangements: customs warehousing, inward processing, processing under customs control, temporary importation and outward processing.
 See the website of the European Commission (http://ec.europa.eu/taxation_ customs/customs/procedural_ aspects /general/centralised_ clearance/index_en.htm).
 See the report of the Project Group on Single Authorisation for Simplified Procedures (SASP), September 2007, pp. 9-10. Available from http://ec.europa.eu/taxation_customs/resources/ documents/customs/policy_ issues/conference_events/ budapest2008/sasp_report. pdf.