Except as provided in subsection (b), an amount withdrawn from an account under this chapter shall be treated as withdrawn on a first-in-first-out basis.
An amount withdrawn from an account under this chapter shall be treated as withdrawn on a last-in-first-out basis if it is—
(1) a nonqualified withdrawal for research, development, and design expenses incident to new and advanced vessel design, machinery, and equipment; or
(2) an amount treated as a nonqualified withdrawal under section 53510(d) of this title.
(Pub. L. 109–304, § 8(c), Oct. 6, 2006, 120 Stat. 1599.)