provided. Substantial nexus (referred to generally as simply "nexus") is a general U.S. Constitutional requirement that is subject to interpretation, generally by the state's comptroller or tax office, and often in administrative "letter rulings". In Quill Corp. v. North Dakota the Supreme Court of the United States confirmed the holding of National Bellas Hess v. Illinois that a corporation or other tax entity must maintain a physical presence in the state (such as physical property, employees, officers) for the state to be able to require it to collect sales or use tax. The Supreme Court's physical presence requirement in Quill is likely limited to sales and use tax nexus, but the Court specifically stated that it was silent with respect to all other types of taxes ("Although we have not, in our review of other types of taxes, articulated the same physical-presence requirement that Bellas Hess established for sales and use taxes, that silence does not imply repudiation of the Bellas Hess rule."). Whether Quill applies to corporate income and similar taxes is a point of contention between states and taxpayers. The "substantial nexus" requirement of Complete Auto, supra, has been applied to corporate income tax by numerous state supreme courts. Apportionment The courts have held that the requirement for fair apportionment may be met by apportioning between jurisdictions all business income of a corporation based on a formula using the particular corporation's details. Many states use a three factor formula, averaging the ratios of property, payroll, and sales within the state to that overall. Some states weight the formula. Some states use a single factor formula based on sales. State capital gains taxes Most states tax capital gains as ordinary income. Most states that do not tax income (Alaska, Florida, Nevada, South Dakota, Texas, and Wyoming) do not tax capital gains either, nor do two states (New Hampshire and Tennessee) that do or did tax only income from dividends and interest. History The first state income tax, as the term is understood today in the United States, was passed by the State of Wisconsin in 1911 and came into effect in 1912. However, the idea of taxing income has a long history. Some of the English colonies in North America taxed property (mostly farmland at that time) according to its assessed produce, rather than, as now, according to assessed resale value. Some of these colonies also taxed "faculties" of