The statutory history line at the end of each federal statute tells you when that statute was enacted, when it was amended, and by which Public Law(s).
The history line for a federal statute is easier to read than the history line for a South Carolina statute. The history line for a statute in the U.S. Code begins with the Public Law number and date it was enacted, along with the citation where the Public Law was published in the United States Statutes at Large. The same information follows for all amendments to the statute, in chronological order.
For example, consider the statutory history line for the whistleblower statute below:
The history line tells you that 18 U.S.C. § 1514A was enacted on July 30, 2002 by Public Law No. 107-204, title VIII, § 806(a) of the Act, which was published in volume 116 of the United States Statutes at Large on page 802. That same history line also tells you that 18 U.S.C. § 1514A was amended on July 21, 2010 by Public Law No. 111-203, title IX, §§ 922(b), (c), which was published in volume 124 of the United States Statutes at Large on pages 1848 and 1852.