In Arkansas Electric Cooperative Corp. v. Arkansas Pub. Serv. Comm'n, 461 U. S. 375 (1983), the Supreme Court considered whether to "follow the mechanical test set out in Attleboro, or the balance-of-interests test applied in our Commerce Clause cases." 461 U. S., at 390-391. The Supreme Court first observed that "the principle of stare decisis counsels us, here as elsewhere, not lightly to set aside specific guidance of the sort we find in Attleboro. " Id., at 391. In deciding to reject the Attleboro analysis, the Supreme Court was influenced by the fact that the "mechanical test" was "anachronistic," that the Court had rarely relied on the test, and that we could "see no strong reliance interests" that would be upset by the rejection of that test. 461 U. S., at 391-392. In Arkansas Elec. Cooperative Corp. v. Arkansas Pub. Serv. Comm'n, 461 U. S. 375 (1983), the Supreme Court rejected the bright-line distinction between wholesale and retail sales drawn by these older cases and concluded that state regulation of wholesale sales of electricity transmitted in interstate commerce is not precluded by the Commerce Clause. Reasoning that utilities should not be insulated from our contemporary dormant Commerce Clause jurisprudence by formalistic judge-made rules, id., at 391, the Supreme Court looked instead to "`the nature of the state regulation involved, the objective of the state, and the effect of the regulation upon the national interest in the commerce,' " id., at 390 (quoting Illinois Natural Gas Co. v.Central Ill. Public Service Co., 314 U. S. 498, 505 (1942)), to determine whether States have a sufficient interest in regulating wholesale rates within their borders, and had no problem concluding that States do indeed have such an interest, with the result that state regulation of wholesale rates is not precluded by the Commerce Clause (in the absence of pre-emptive congressional action), id., at 394-395.