Calculated spectrum-averaged cross sections are presented for all of the reactions in the International Reactor Dosimetry File (IRDF-82) using the ten benchmark neutron fields that were distributed with IRDF-82. Comparisons to experimentally measured spectrum-averaged cross sections are presented for the 252Cf and 235U thermal fission spectra. This comparison shows that the difference between the measured and calculated spectrum averages is still much larger than the experimentally quoted uncertainties. This indicates that more precise knowledge of these spectra and further evaluations are still needed.