Pub. L. 110–234 and Pub. L. 110–246 made identical amendments to this section. The amendments by Pub. L. 110–234 were repealed by section 4(a) of Pub. L. 110–246.

2008—Subsec. (a). Pub. L. 110–246, § 4201(a), reenacted subsec. heading without change, designated existing provisions as par. (1), inserted par. heading, substituted “for each of the fiscal years 2008 through 2012, the Secretary shall purchase a dollar amount described in paragraph (2)” for “for each of fiscal years 2002 through 2007, the Secretary shall purchase $140,000,000”, and added par. (2).

2002—Subsec. (a). Pub. L. 107–171 substituted “2002 through 2007” for “1997 through 2002” and “$140,000,000” for “$100,000,000”.

Amendment of this section and repeal of Pub. L. 110–234 by Pub. L. 110–246 effective May 22, 2008, the date of enactment of Pub. L. 110–234, except as otherwise provided, see section 4 of Pub. L. 110–246, set out as an Effective Date note under section 8701 of this title.

Amendment by section 4201(a) of Pub. L. 110–246 effective Oct. 1, 2008, see section 4407 of Pub. L. 110–246, set out as a note under section 1161 of Title 2, The Congress.

Pub. L. 107–171, title IV, § 4126(b), May 13, 2002, 116 Stat. 328, provided that: “The amendments made by this section amending this section] take effect on October 1, 2001.”