The benchmark experiments, performed in a plutonium-fueled critical assembly (ZPR-6 Assembly 7) in support of the fast reactor demonstration plant program, were used, in conjunction with a statistical method of correlation, as a source of suggestions for possible modifications to multigroup neutron cross-section sets based on ENDF/B files. Version 1 of these files was a starting point in the correlation procedure. The general trends of the results (lower 238U capture cross section and 235U fission cross section, higher 239Pu capture to fission ratio, with respect to ENDF/B Version 1 data) are discussed, and the suggested multigroup cross-section adjustments are compared with recent evaluations. Calculations of keff, and of the ratios of 238U and 235U fission rate and of 238U capture rate to 239Pu. fission rate, using the proposed adjusted set, give results in good agreement with the experiments.