  This work summarizes the current status of the measured semileptonic
branching fractions $B^{0,+} \to X_c \mu\nu$. The sum of exclusive measurements
is compared with the inclusive determination, accounting for isospin
extrapolation. Further derived quantities are computed, taking into account
different explanations for the unmeasured components of the total branching
fraction. These quantities focus on the charge breakdown of the final states,
and are designed for use as inputs or comparisons in future experimental
measurements.
