[en] The decay data of all experimentally identified fission product nuclides included in the JNDC FP Decay Data File are reviewed in detail, since the missing of beta-transition to unobserved highly excited states in the daughter nucleus is considered to be probable in some cases even for nuclides with small Q_β. Thus the decay energies of 127 nuclides or metastable states except for ⁸⁸Rb and ¹⁴³La revised previously are reevaluated. The results of summation calculations based on the revised JNDC FP Decay Data File modified by the present evaluation are in much better agreement with experimentally measured decay power curves than previous ones. Especially, the discrepancy remained for cooling times from a few hundreds to about 1500 seconds is removed. And the agreement is kept within about 5 % for wide range of cooling times. (author)