In software products, often the failure rate decreases after installation, eventually reaching a steady state. The time it takes for a product to reach its steady state reliability depends on different product parameters. In this paper we propose a new metric for software products called stabilization time which is the time taken after installation for the reliability of the product to stabilize. This metric can be used for comparing products, and can be useful for organizations and individuals using the product as well as for the product vendor. We also present an approach for determining the stabilization time of a product from its failure and sales data. We apply the approach to three real life products using their failure and sales data after release.