State governments rely on sales and use taxes for approximately half (48.2%) of their total tax revenue — or approximately $715.2 billion in FY2004. Local governments derived 11.4% of their tax revenue or $44.6 billion from local sales and use taxes in FY2003. Both state and local sales taxes are collected by vendors at the time of transaction and are levied at a percentage of a product’s retail price. The two major Supreme Court decisions in this area are National Bellas Hess, Inc. v. Illinois Department of Revenue, and Quill Corp. v. North Dakota.