The first volume of this report examines the existing measures of high school completion and the newly proposed proxy measures. This includes a description of the computational formulas, the data required for each indicator, the assumptions underlying each formula, the strengths and weaknesses of each indicator relative to a true cohort on-time graduation rate, and a consideration of the conditions under which each indicator does or does not work. The second volume of this report provides documentation of the technical work that the Department leadership used to select an interim graduation rate. Appended are: (1) Description of Common Core of Data, Private School Universe Survey, and Current Population Survey; and (2) Formulas and Details of Each Indicator. (Contains 12 tables and 10 figures.) [For Volume 2, see ED493142.]