Section, acts Aug. 16, 1954, ch. 736, 68A Stat. 306; Sept. 2, 1958, Pub. L. 85–866, title I, § 46(b), 72 Stat. 1642; Feb. 26, 1964, Pub. L. 88–272, title II, § 206(b)(4), 78 Stat. 40; Jan. 2, 1975, Pub. L. 93–597, § 6(a), 88 Stat. 1953; Mar. 29, 1975, Pub. L. 94–12, title II, § 207, 89 Stat. 32; Oct. 4, 1976, Pub. L. 94–455, title XIX, §§ 1901(a)(129), 1906 (b)(13)(A), 90 Stat. 1785, 1834; May 23, 1977, Pub. L. 95–30, title I, § 102(b)(13), 91 Stat. 138; Nov. 6, 1978, Pub. L. 95–600, title IV, §§ 404(c)(5), 405 (a)–(c)(1), 92 Stat. 2870, 2871; Nov. 8, 1978, Pub. L. 95–615, title II, § 206, 92 Stat. 3107; Aug. 13, 1981, Pub. L. 97–34, title I, §§ 112(b)(4), 122 (a), (b), 95 Stat. 195, 197; July 18, 1984, Pub. L. 98–369, div. A, title X, § 1053(a), 98 Stat. 1045; Oct. 22, 1986, Pub. L. 99–514, title XVIII, § 1878(g), 100 Stat. 2904; Nov. 10, 1988, Pub. L. 100–647, title VI, § 6002(a), 102 Stat. 3684, related to rollover of gain on sale of principal residence.