To amend the Internal Revenue Code of 1986 to permanently extend the 50-percent bonus depreciation added by the Jobs and Growth Tax Relief Reconciliation Act of 2003.

Amends the Internal Revenue Code to: (1) permanently extend the 50 percent and 30 percent bonus depreciation for certain original use property, including water utility property, computer software, or qualified leasehold improvement property; (2) permit the use of the percentage of completion accounting method for computing certain depreciation allowances; and (3) allow corporate taxpayers to elect an increased refundable alternative minimum tax credit in lieu of taking a bonus depreciation deduction.