[Bill_G]

Trimet ridership stats are derived from the passenger counters in the stairwells of each bus. The counts are accumulated during a run, and downloaded when the operator turns in his pouch. Manual audits are a thing of the past. However, the system has a well known error factor of at least 3 percent. It is not uncommon for an empty bus to return to the yard with 20 passengers aboard after a full days run. "More on's than off's" used to be a common maintenance issue. Now it's only addressed if no passenger count data is accumulated during the day because no fix was found for the accumulated errors. The technology is just not there to be 100 percent accurate.

And privacy issues drive the anonymity factor for now. If a smart card could be tracked without linking to an individual, then it would be accepted and the data brought into the system. We could follow a particle in the tube without knowing who they are. If people get the hint that a card identifies them, the technology would not be used.