[13] This section describes the bill known as PL 108-357 (H.R. 4520), “American Jobs Creation Act of 2004.” For the full text of the bill, see web site http://frwebgate. access.gpo.gov/cgi-bin/getdoc.cgi?dbname=108_cong_ bills&docid= f:h4520enr.txt.pdf.

[14] Carry-back refers to the practice of using a credit from taxable income for a prior tax period. Carry-forward refers to using a credit in a future taxable period.

[15] The reference price for a taxable year is the price in the calendar year preceding the claendar year in which the taxable year begins. This price is determined as: (a) in the case of qualified crude oil production, the Secretary of the Treasury’s estimate of the average annual wellhead price per barrel for all domestic crude oil (the price of which is not subject to regulation by the United States), and (b) in the case of qualified natural gas production, the Secretary of the Treasury’s estimate of the average annual wellhead price per 1,000 cubic feet for all domestic natural gas.

[16] Extension of the in-service date for wind, closed-loop biomass, and poultry litter through 2005 was also part of the Working Families Tax Relief Act of 2004.

[17] Transmix is the mixture in a pipeline at the interface between adjoining batches of petroleum product with dissimilar physical characteristics, which cannot be absorbed into adjoining batches.