In the United States economy most markets can be classified into four different markets structures. But, each and every market in the United States is completely unique from the others. Generally the best type of market structure for the general public is per- fect competition because it creates the lowest possible price for the public. There are some exceptions were perfect competition isn’t the best choice for the public on account of various reasons. The United States Postal Service is one of them and since the Postal Service ....