  Fluctuations of various observables in heavy-ion collisions at
ultra-relativistic energies have been extensively studied as they provide
important signals regarding the formation of a Quark-Gluon Plasma (QGP).
Because of the large number of produced particles in each event, a detailed
study of event-by-event multiplicity fluctuations has been proposed as one of
the signatures of the phase transition. In addition, the understanding of
multiplicity fluctuations is essential for other event-by-event measurements.
In the present work, we have calculated the scaled variance ($\omega_{\rm
ch}=\sigma^{\rm 2} / \mu$) of the charged-particle multiplicity distributions
as a function of centrality in Pb-Pb collisions at LHC energies. Here, $\mu$
and $\sigma$ denote the mean and the width of the multiplicity distributions,
respectively. The trend of scaled variances as a function of centrality is
presented and discussed. Volume fluctuations play an important role while
measuring the multiplicity fluctuations, which are also discussed. The results
are expected to provide vital input to theoretical model calculations.
