In the 1880s, the West Publishing Company started its National Reporter System (NRS), which is a family of regional reporters, each of which collects select state court opinions from a specific group of states. The National Reporter System is now the dominant unofficial reporter system in the U.S., and 21 states have discontinued their own official reporters and certified the appropriate West regional reporter as their official reporter. West and its rival, LexisNexis, both publish unofficial reporters of U.S. Supreme Court opinions. West also publishes the West American Digest System to help lawyers find cases in its reporters. West digests and reporters have always featured a "Key Numbering System" with a unique number for every conceivable legal topic.