  We have just entered an era of precision measurements for $B_s$-decay
observables. A characteristic feature of the $B_s$-meson system is
$B^0_s$--$\bar B^0_s$ mixing, which exhibits a sizable decay width difference.
The latter feature leads to a subtle complication for the extraction of
branching ratios of $B_s$ decays from untagged data samples, leading to
systematic biases as large as O(10%) that depend on the dynamics of the
considered decay. We point out that this effect can only be corrected for using
information from a time-dependent analysis and suggest the use of the effective
$B_s$ decay lifetime, which can already be extracted from the untagged data
sample, for this purpose. We also address several experimental issues that can
play a role in the extraction of effective lifetimes at a hadron collider, and
advocate the use of the $B_s$ branching ratios, as presented in this note, for
consistent comparisons of theoretical calculations and experimental
measurements in particle listings.
