@Aske Bisgaard Vammen I may be missing the point entirely, but I assume that an exporter, imports parts and ingredients for a cost A, assembles them using domestic labor, parts and machinery for a cost B, exports the finished product after incurring other costs C. Finally he or she gets paid D, and makes a profit = D-C-B-A. D is money coming into the country and adding to the money supply, whereas A is money leaving the country, and reducing the money supply. The difference D-A is the balance of trade. Other examples are a (Chinese) mining company who digs up minerals at a cost C, has no need for imports, but sells the minerals abroad for D, and the balance D-C is positive for the mining company. A retailer imports goods (from China) for a certain cost and sells them domestically. In which case the balance is negative. So trade adds to the money supply whenever total receipts from exports are greater than the total cost of imports... Obviously these are very simple schemes, ignoring exchange rates, the balance with different countries etc etc... but at least this is what I have understood until now...