Punctuality measures

Robert H Foster ( Open Access, RAIL 870) blames poor regulation for operators failing to hold trains to await late-running connecting services. He has a point, but I think the system of punctuality targets is largely to blame.

Punctuality is measured using the Public Performance Measure (PPM), under which train operators are expected to achieve a certain percentage of their services arriving at their destinations within either five or ten minutes of their scheduled times.

The trouble with this sort of measure is that once a train is running so late that there is no longer a reasonable expectation of it complying with its target, there is no longer any incentive for managers to minimise further delays. The train is already non-compliant as far as the PPM is concerned, and nothing that management can do will alter this.

Further, there is a disincentive to maintain connections as trains delayed awaiting connections are themselves likely to become non-compliant, whereas if they are allowed to start on time, despite the inconvenience to connecting passengers, they should remain PPM-compliant.

Clearly the system is not working in a way that benefits passengers. A much better system would be one that calculates the average number of minutes late that an operator’s services run. Success or failure could then be measured in terms of average lateness.

Importantly, such a system would retain the incentive to minimise further delays even when a train is already running late. A train that arrives at its destination 30 minutes late will clearly have a more detrimental effect upon the operator’s average lateness figure than one arriving 15 minutes late.

An advantage of the present system is that it also accounts for trains that are cancelled for all or part of their journeys, but there is no reason why this aspect of the PPM could not be separated from the punctuality aspect. More useful punctuality PPMs would then result. Rick Zaple, Cardiff