Here is the sequence of transactions among Citibank overseas branches on Dec. 8: 1.) Citibank's Zurich branch buys $35 million from its Nassau branch, giving the Nassau branch a profit of 563,500 Swiss francs. 2.) The Zurich branch then buys the francs from the Nassau branch at fractionally fewer francs per dollar than the first transaction, giving the Nassau branch a $250,000 profit. 3.) The Aurich branch then resells the $35 million to the Nassau branch, but this time West German marks are used, giving the Nassau branch a profit of 647,000 marks. 4.) Then the Zurich branch buys the 647,000 marks representing the Nasasau bank's profit at a rate that makes the Nassau branch's profit on the earlier deal $270,000. 5). $500,000 in profits have been "parked" in Nassau. 6.) The Frankfurt branch sells $70 million to the Nassau branch for German marks. 7.) The Zurich branch then buys this $70 million from the Nassau branch for German marks for fractionally more marks per dollar than the rate used in the Frankfurt branch sale, leaving the Nassau branch with a $500,000 profit. 9.) The Zurich branch then tells the New York office to credit the Zurich branch with a $1 million profit on the internal bookkeeping system. 10.) For tax purpose, however, the profits will be allocated to the Nassau branch.