62 For a discussion on the importance and difficulty of measuring compliance with international agreements see Downs, George W., Rocke, David M. Barsoom, Peter N., Is the Good News Compliance Good News About Cooperation?, 50 Int`l Org. 379 (1996). The concept of treaties existed in the early periods of human civilizations. However, in the 20th century, new rules and laws were recognized and formulated for treaties. The Vienna Convention on Treaty Law (1969) contains the rules on treaties between states and the Vienna Convention on the Law of Treaties between States and International Organizations or between international organizations (1986). That is why these two documents form the basis of the formulation of treaties in international law. The fact that the guide contains a list of contracts indexed in TIF in the year prior to the year prior to publication, but which are no longer indexed thereafter, is a priority of this analysis. The guide helps to identify the agreements that have been removed from the TIF and the year of the deletion. The U.S. State Department considers that an agreement that is on the previous year`s tIF list but is not listed this year is no longer in effect by the State Department. The footnote 70 deletions is based on one of four reasons, although the TIF does not indicate the reason for a particular deletion. These grounds apply (1) on the basis of the terms of the contract; (2) termination; (3) replacement with another agreement; or (4) termination.

Footnote 71 The President may enter into an international agreement under a treaty that has entered into force with the Senate and the approval of the Senate and whose provisions constitute an authorization of the executive branch for the agreement without further intervention by Congress; In the United States, executive agreements are made exclusively by the President of the United States. They are one of three mechanisms through which the United States makes binding international commitments. Some authors view executive agreements as treaties of international law because they bind both the United States and another sovereign state. However, under U.S. constitutional law, executive agreements are not considered treaties within the meaning of the contractual clause of the U.S. Constitution, which requires the Council and the approval of two-thirds of the Senate to be considered a treaty. Contracts and executive agreements are instruments of domestic law. These procedures allow the United States to be part of an international agreement. Figure 3 shows that there is a 14% probability for an agreement at the end of the observation period, provided it is in effect by then.

For executive agreements, this probability is 40%. Similarly, there is a 15 per cent probability that a contract will be broken between 1982 and 2012, while the probability is 50 per cent for executive agreements. The president can reach an international agreement on any subject within his constitutional authority, as long as the agreement is not in contradiction with the legislation passed by Congress in the exercise of its constitutional authority. The constitutional sources of the President`s authority to conclude international agreements are: 69 See z.B. U.S. Department of State, A Guide to the United States Treatys treaty in force, at vii (Igor I.