This paper ranks 155 U.S. Catholic universities and colleges which produced the highest number of students in the 1960s, 1970s, and 1980s who later earned doctorates, and analyzes various trends for these decades. The study first provides trend information followed by a ranking analysis among single-gender Catholic institutions. Among the facts is the finding that, with the exception of Providence College in Rhode Island, all Catholic institutions which ranked in the top 30 institutions for awarding doctoral degrees were founded prior to the turn of this century. The top school for all three decades combined is the Indiana's University of Notre Dame. Other data reveal that: (1) the northern and northeastern regions of the continental United States are where the top 21 Catholic institutions are located; (2) Manhattan College in New York is the only single-gender (all-men) institution appearing in the top 10 rankings of U.S. Catholic institutions producing the most doctoral graduates during the three decades, and (3) all-women institutions all appear below the top 50 rankings. (Contains 13 references.) (GLR)