In Model 3-2, the long-run (a.k.a. steady-state ) expected total time in system of a loan application is 20 hours, which can be derived from queueing theory, namely, exponential queues in series. This means that in a mythical simulation of inf nite length (rather than the 160 hours we ran), loan applications would average 20 hours from entry to exit; there’s no uncertainty associated with this 20, since this mythical run is inf nitely long. Another way of looking at it is that a loan application arriving after the system has already been in operation for a long (inf nite) time would have an expected total time in system of 20 hours. In Section 3.5.1, we saw that Model