What Factors Entice States to Manipulate Corporate Income Tax Apportionment Formulas?

Numerous states have altered the sales factor weight in their corporate income tax (CIT) apportionment formulas. We are among the first to examine which political and economic factors are important in determining whether and when states manipulate sales factor weights. We apply survival model techniques to a panel of state-level data for the years 1985−2012. Our most striking result is that a higher CIT rate is associated with faster movement to a higher sales factor weight. Perhaps indicating that, for economic development, states use sales factor manipulation in lieu of reducing CIT rates broadly, or alternatively, that states raise sales factor weights to compensate for higher statutory CIT rates. Results also indicate that stronger growth in the CIT base and in non-corporate tax revenues hasten sales factor weight increases. Democratic control of the state government and gubernatorial election years are also important in the timing of sales factor manipulation.