Standard deviation

Hello all, I have a basic question, when I tally something (ex flux), I get the result with a mean and a standard deviation (std_dev), so is that indicate mean +/- std_dev or std_dev% ?
Richard

According to openmc.lib.tally source code, in def global_tallies, the standard deviation calculation doesn’t have the mean as a denominator. So I would say the units of standard deviation are the same as the mean, rather than a %.

Thanks for your reply, it must be helpful