Decay-rate tally of OpenMC

Hi all,
The specification of “decay-rate” tally in the user’s guide is :

The delayed-nu-fission-weighted decay rate where the decay rate is in units of inverse seconds.

I’m confused about the meaning of “The delayed-nu-fission-weighted”. Does it means that the real decay rate is obtained by the way of “decay-rate tally” divide by “delayed-nu-fission tally” ?
Any reply will be appreciated!

Best Regards
Benjamin