In converting matrices from one suite into another it is important to remember that different suites may have different conventions as regards units. In particular recall that SATURN prefers to define trip matrices in units of pcus/hr whereas other suites may use vehicles/hr. Thus it may be necessary, having read an input data file into MX, to undertake some further factoring to correct for units. Cost matrices, which might be in monetary units or generalised time units, are another case in point.