Does decrease in copying cost support copyright term extension?

Copyright duration has been or is being extended in many countries. Technological and demographical changes were cited by a US Senate report to argue for US copyright term extension. This paper analyzes the validity of the arguments. Simulation of a model of the information product market indicates that a decrease in copying cost of information products due to digital technologies calls for a reduction of copyright duration. Partial support is found for the argument that longer life expectancy and delayed child-bearing may support copyright term extension. Furthermore, an increase in demand for information products is found to call for reduction in copyright duration.