The Commerce Clause of the U.S. Constitution grants Congress the power "to regulate Commerce . . . among the several States." U.S. Const. Art. I, 8 cl. 3. the Indiana Court has noted that: although the Commerce Clause is silent as to how much economic regulatory power a state retains, it has been applied to prevent states from discriminating against out-of-state economic interests or from benefiting instate interests. The U.S. Supreme Court has rejected the view, however, that interstate commerce is immune from state taxation. Consequently, a state tax will withstand a Commerce Clause challenge if it: (1) is applied to an activity with a substantial nexus with the taxing state; (2) is fairly apportioned; (3) does not discriminate against interstate commerce; (4) is fairly related to the services provided by the State. Anderson, 758 N.E.2d at 601 (citing Complete Auto Transit, Inc. v. Brady, 430 U.S. 274, 279, 97 S.Ct. 1076, 51 L. Ed. 2d 326 (1977), reh'g denied). Moreover, merely to characterize Indiana's use tax as facially nondiscriminatory, as the Department has done, does not save the use tax from violating the Commerce Clause. See American Trucking Ass'ns., Inc. v. Schemer, 483 U.S. 266, 281, 97 L. Ed. 2d 226, 107 S. Ct. 2829 (1987) (holding that the Commerce Clause may be implicated even though state provisions do not allocate tax burdens in a facially discriminatory manner). Thus, the Department's argument that the same tax rate applies equally to all Indiana taxpayers is unavailing; the use tax directly discriminates against interstate commerce regardless of whether the same rate uniformly applies to all taxpayers.