8.75 An important aspect of quality is that the concepts, definitions and classifications used should be consistent with those of related statistics. Australia's international merchandise export and import statistics have been compiled in broad agreement with UN guidelines for many years. The relevant international standards are widely used throughout the world, ensuring a broad level of consistency between the trade statistics of participating countries. The international standards for international merchandise trade statistics are also closely harmonised with those for related data sets, i.e. BPM5 and SNA93 for Balance of Payments and National Accounts statistics, respectively.
8.76 Changes to the concepts used to compile international merchandise trade statistics occasionally occur, and care should be taken to make allowances for such changes when comparing statistics before and after the changes. The effect of conceptual changes should not be seen as detracting from the quality of the statistics, as, if no changes at all were made, the statistics may progressively become less relevant and useful. In recent years, conceptual changes have not had any major effects on Australia's trade statistics.
8.77 In late 1998, the UN issued revised concepts and definitions for the compilation of international merchandise trade statistics designed to facilitate the production of 'nationally useful and internationally comparable' data (IMTS, Rev.2). Some of the changes made were to better harmonise with BPM5 and SNA93. Minor coverage changes resulted from the 1998 revisions and these were implemented by Australia on 1 July 1999. The UN recommended, amongst other things, changes in the treatment of two types of goods: those subject to lease; and those used as carriers of information and software. Their impact was detailed in Revisions to Standards for International Trade Statistics in International Merchandise Trade, Australia June Quarter 1999 (Cat. no. 5422.0).