  We numerically investigate the statistical properties of Wigner delay time in
Anderson disordered 1D, 2D and quantum dot (QD) systems. The distribution of
proper delay time for each conducting channel is found to be universal in 2D
and QD systems for all Dyson's symmetry classes and shows a piece-wise power
law behavior in the strong localized regime. Two power law behaviors were
identified with asymptotical scaling ${\tau^{-1.5}}$ and ${\tau^{-2}}$,
respectively that are independent of the number of conducting channels and
Dyson's symmetry class. Two power-law regimes are separated by the relevant
time scale $\tau_0 \sim h/\Delta$ where $\Delta$ is the average level spacing.
It is found that the existence of necklace states is responsible for the second
power-law behavior ${\tau^{-2}}$, which has an extremely small distribution
probability.
