5.1 International merchandise trade statistics (IMTS) measure quantities and values of goods that, by moving into or out of an economy, add to or subtract from a nation’s material stock of goods. IMTS are compiled from report forms or from electronic transmissions sent by importers and exporters (or their agents) to the customs and excise agency or to the IMTS compiler, which in many cases would be the statistical agency. Balance of payments compilers in most economies rely on IMTS to compile the goods item in the balance of payments, and in some economies it is used in compiling other items in balance of payments accounts as well.