Opposite to economically efficient trade creation effect, the trade diversion flow is cost-inefficient compared with the rest of the world. Balance between trade creation and trade diversion effects due to the creation of economic union makes the union either economically efficient (positive balance) or inefficient (negative balance). It is based on the fact that unification of states usually applies mergers of more than 1 sector in economy (even European Coal and Steel Union, which had 2 sectors only) leading to the creation of either trade creation or diversion effects.