"The Nation’s first copyright statute, enacted in 1790, provided a federal copyright term of 14 years from the date of publication, renewable for an additional 14 years if the author survived the first term. The 1790 Act’s renewable 14-year term applied to existing works and future works alike. Congress expanded the federal copyright term to 42 years in 1831 and to 56 years in 1909. Both times, Congress applied the new copyright term to existing and future works. In 1976, Congress altered the method for computing federal copyright terms, providing that protection for works created by identified natural persons would run from creation until 50 years after the author’s death. For published works with existing copyrights as of January 1, 1978, the 1976 Act granted a copyright term of 75 years from the date of publication, a 19-year increase over the 56-year term applicable under the 1909 Act. The CTEA installed the fourth major duration extension of federal copyrights, enlarging the terms of all existing and future copyrights by 20 years."