The impact of depreciation savings on investment: Evidence from the corporate Alternative Minimum Tax

•I characterize a firm's investment incentives in the presence of AMT.•I show that firms, the investment incentives of which are characterized by AMT system around 1999, increase investment significantly compared to firms never subject the AMT.•I find the responsiveness coefficient estimated to be somewhat larger than the previous estimates.•I conclude that the new identification strategy and high salience of AMT reform are likely the main factors that account for differences.

Over the past decade, the United States has offered investment incentives in the form of larger depreciation savings, namely, bonus depreciation. The neoclassical investment model implies that investment responds to changes in depreciation savings, but there have been few direct attempts to investigate this implication. This paper examines investment patterns surrounding the 1999 shortening of the Alternative Minimum Tax (AMT) depreciation recovery periods, finding strong evidence that firms subject to the AMT increase investment in response to the AMT reform. The empirical results show that firms subject to the AMT increase their investment, measured as the ratio of capital expenditures to capital stock, by around 0.0418 to 0.0622, compared to firms subject to the regular tax. Given their average annual investment rate of approximately 0.27 during this period, the results imply a relative increase in investment of 15%--23%. By contrast, I find that the 2002 introduction of bonus depreciation, available both for firms subject to the regular tax and for firms subject to the AMT, affects both groups of firms similarly. The estimation uses an empirical specification developed from the Summers (1981) tax-adjusted q model, and the results imply that the responsiveness of investment to the tax term is somewhat larger than previously estimated.