The regional and community parliaments and governments have jurisdiction over transportation, public works, water policy, cultural matters, education, public health, environment, housing, zoning, and economic and industrial policy. They rely on a system of revenue-sharing for funds. They have the authority to levy a very few taxes (mostly surcharges) and to contract loans. Moreover, they have obtained exclusive treaty-making power for those issues coming under their respective jurisdictions. Of total public spending (interest payments not considered), more than 30% is authorized by the regions and communities, although their financing comes for over 80% from national Belgian budgets; at the same time, the national government controls 100% of social security, and strictly limits the taxation policy by the federalized entities. As a result, Belgian institutions still control over 90% of the effective, global taxation levels on individuals and companies.