1. Such agreements shall be amended by mutual agreement between the Parties or (a) The designated airline(s) of each Party shall make available to the aviation authorities of the other Party, at least thirty days in advance, copies of the working time schedules, including any changes, as well as any other similar relevant information on the operation of their air services under this Agreement. 7. The Delegation of the United States drew attention to the significant traffic between Member States and the considerable annual growth, while highlighting the difficulties faced by its international airlines in operating that traffic. It has also been pointed out that, in all these circumstances, especially with regard to lines of this length, the traffic of the third and fourth freedoms is necessarily relatively low when approaching the ends of the lines and, therefore, the traffic of the fifth freedom must be relatively large if an airline is to operate economically. . . .