Article 150 Contribution classes (Const. 21; Gen. Regs 131, 145, 146, 147 and 148)

1. Member countries shall contribute to defraying Union expenses according to the contribution class to which they belong. These classes shall be the following:

class of 50 units;

class of 45 units;

class of 40 units;

class of 35 units;

class of 30 units;

class of 25 units;

class of 20 units;

class of 15 units;

class of 10 units;

class of 5 units;

class of 3 units;

class of 1 unit;

class of 0.5 unit, reserved for the least advanced countries as listed by the United Nations and for other countries designated by the Council of Administration.

2. Notwithstanding the contribution classes listed in paragraph 1, any member country may elect to contribute a higher number of units than that corresponding to the contribution class to which it belongs, for a minimum term equivalent to the period between Congresses. The announcement of a change shall be made at the latest at Congress. At the end of the period between Congresses, the member country shall return automatically to its original number of contribution units unless it decides to maintain its contribution of a higher number of units. The payment of additional contributions will increase the expenditure accordingly.

3. Member countries shall be included in one of the above-mentioned contribution classes upon their admission or accession to the Union, in accordance with the procedure laid down in article 21.4 of the Constitution.

4. Member countries may subsequently be placed in a lower contribution class, on condition that the request for this change is sent the International Bureau at least two months before the opening of Congress. Congress shall give a non-binding opinion on these requests for a change in contribution class. The member country shall be free to decide whether to follow the opinion of Congress. The final decision of the member country shall be transmitted to the International Bureau Secretariat before the end of Congress. This change request shall take effect on the date of the entry into force of the financial provisions drawn up by Congress. Member countries that have not made known their wish to change contribution class within the required time shall remain in the class to which they belonged up to that time.