The budget for the two years 2000-2001 is $2,535 million. The main source of funds is the contributions of Member States, which are assessed on a scale approved by the General Assembly. The fundamental criterion on which the scale of assessments is based is the capacity of countries to pay. This is determined by considering their relative shares of total gross national product, adjusted to take into account a number of factors, including their per capita incomes.
In addition, countries are assessed -- in accordance with a modified version of the basic scale -- for the costs of peacekeeping operations, which stood at around $2 billion in 2000.