  We introduce a qauantitative measure of spin-charge separation, $\zeta (t)$
which is based on the difference between the fluctuations with respect to
background of the spin and charge profiles at any time t and is suitable for
studying the non-equilibrium dynamics of excitations in strongly correlated
systems. This quantity is not only a direct measure of the spin-charge
separation in strongly correlated systems, but its long time behaviour can
further serve as a possible order parameter for the interaction induced (Mott)
insulating state. Within the nu- merically exact diagonzalization we calculate
this quantity for the two dimensional Hubbard model away from Half filling. Our
quantitative measure in chain, ladder and two-dimensional geometries gives the
same order of magnitude for the quantity of spin-charge separation. Furthermore
from the temporal behaviour of $\zeta (t)$ a threshold time can be identified
that provides clues onto the breakdown of underlying Mott insulating phase.
