  The effects of saving and spending patterns on holding time distribution of
money are investigated based on the ideal gas-like models. We show the
steady-state distribution obeys an exponential law when the saving factor is
set uniformly, and a power law when the saving factor is set diversely. The
power distribution can also be obtained by proposing a new model where the
preferential spending behavior is considered. The association of the
distribution with the probability of money to be exchanged has also been
discussed.
