D. Legal acts governing the content and availability of data sources
2.12. If the statistics are based on administrative records, it is advisable to include a paragraph in the legal text that gives the statistical office the legal right to access those data sources. Such language would facilitate cooperation among the institutions involved, contributing to timely data delivery and ensuring transparency.
2.13. One of the administrative sources relevant to trade in services statistics is customs records. The World Customs Organization (WCO) is the international platform through which countries reach legal agreements on customs regulations, including those relevant to the compilation of data on international freight and insurance related to the transportation and customs clearance of goods. Among the most relevant WCO conventions is the revised Kyoto Convention on the Simplification and Harmonization of Customs Procedures, which provides standards for such customs procedures as the inward and outward processing of goods; those must be understood when compiling, for example, manufacturing services on physical inputs owned by others. WCO also participates in setting legal provisions for the customs valuation of goods, which has significant consequences for the valuation of the related international transactions in services. In that context, it should be noted that it is the responsibility of WTO to formally adopt such provisions and amend them as necessary.
2.14. Much of the data needed for measuring the international supply of services come from statistical surveys or from an international transactions reporting system (ITRS), formerly known as a foreign exchange record system. Most examples of such systems evolved as by-products of foreign exchange control acts, which were, and in many instances remain, legally binding. Statistical compilers should be aware of the contents of the legal provisions underpinning the national ITRS and make full use of them. In addition, as an increasing number of countries are planning to remove certain legal obligations, statistical compilers should prepare themselves well in advance to make necessary adjustments in their data collection arrangements.
2.15. The importance of a well-established legal basis for statistical surveys is recognized and promoted by all concerned international and regional organizations. For example, according to IMF, a good legal authority needs to state that the reporting of statistical information is mandatory, especially for large enterprises. It is good practice to explicitly refer to such legislation in the resident/non-resident trade in services statistics and FATS survey forms.
2.16. Compared to outward FATS, inward FATS is often easier to collect because the relevant enterprises are present in the compiling economy. Often, only information about the foreign-owned share of an enterprise located domestically needs to be collected. That information can, in turn, be linked to existing information in national business statistics. In the case of outward FATS, where the relevant economic entity is located abroad, the legal acts should provide a mandate for statistical compilers to require information from domestic enterprises on their foreign affiliates located in other countries. That aspect might cause difficulties for compilers because of the limited data availability as well as sensitivity to reporting such data. In either case, it is important that compilers have a clear legal mandate for collecting the data.
 The International Convention on the Simplification and Harmonization of Customs Procedures entered into force in 1974 (United Nations, Treaty Series, vol. 950, No. 13561). The revised Kyoto Convention was adopted in June 1999. The provisions contained in the revised Kyoto Convention aim to facilitate trade, but at the same time make customs records a highly standardized and reliable data source for trade statistics across countries. The revised Kyoto Convention comprises a body, general annex and specific annexes.
 Statistical compilers should take note of the rules on customs valuation as set out in the WTO Agreement on Customs Valuation (see International Merchandise Trade Statistics: Concepts and Definitions 2010, (IMTS 2010), Statistical Papers, Series M, No. 52 (United Nations publication, Sales No. E.10.XVII.13), annex D).
 See BPM6 Compilation Guide, para. 2.5.