16.1. Chapter 16 focused on the compilation of additional indicators on the international supply of services, in particular data on the number of persons/trips relevant to modes 2 and 4 and the use of data on services production, prices, employment or sectoral performance indicators. Also, linking trade and business registers offers the potential for the compilation of new types of data. Section A introduces the general purpose of the chapter and Section B provides a summary of good practices with respect to additional indicators on the international supply of services. Section C contains an overview of the compilation of variables on the movements of natural persons under modes 4 and 2 of the supply of services. Section D describes the linking of business and trade registers. Finally, section E lists possible existing additional indicators and the level of detail necessary for a full analysis of services sectors in the context of the international supply of services.