A bill to amend the Internal Revenue Code of 1954 to modify the substantiation requirements for 100 percent qualified business use of passenger automobiles and to provide an exemption for agricultural vehicles from the requirements of section 280F of such Code (relating to limitation on certain property used for personal purposes).

Amends the Internal Revenue Code to provide that where a vehicle is used 100 percent of the time for business purposes, the taxpayer must maintain adequate records or sufficient evidence corroborating the business use of the vehicle (rather than maintaining adequate contemporaneous records as required under current law). Requires the principal user and the employer to sign an affidavit at the beginning of the year as to the intended use of such a vehicle and at the end of the year as to its actual use.

Exempts agricultural vehicles from the rules relating to the limitation on the investment tax credit and depreciation deduction for certain property used for personal purposes.