[en] This report describes a computer-based data file developed from Licensee Event Reports (LERs) of instrumentation and control (I and C) components in United States commercial nuclear power plants for the period January 1, 1976 to December 31, 1981. In addition to the creation of the file, summaries of data contained in the file were made to obtain data for risk assessment and statistical purposes. Gross constant fault (failure and command fault) rates were estimated for major components and channels that provide a direct reactor trip. Explanations, figures, and summary tables of the results are provided. This report updates and supersedes the original May 1981 edition of NUREG/CR-1740