03/04/2013 08:36 BST | Updated 02/06/2013 06:12 BST

Train Punctuality: Are We Measuring the Wrong Thing?

Commuters constantly complain about how awful British train services are.

We complain about ticket prices but are told that the increases are needed to pay for better services in the future and to offset reductions in government subsidies (the jam tomorrow argument).

Commuters also complain about capacity: there are never any seats available, if you manage to get on a train at all. This issue is often met with the dual refrain of suggesting we work more flexibly and that capacity is being increased (using those record increases in fares).

Most of all, however, we complain about delays. Whether it's signal failure, leaves on the line or the wrong kind of snow, there's always a delay of some sort to contend with. The response is often that we're wrong. That services actually run quite well, some lines are among the best in Europe for train punctuality.

Here's a question that's not often asked: what if train punctuality is a false measure? Perhaps commuter punctuality is what we should really care about? Instead of the number of trains getting to stations on time, perhaps we would get more useful information if we tracked the number of people being delivered to stations on time.

The majority of rail journeys occur in two bands during the day, when people are travelling to and from work. If a problem happens in rush hour, it's possible that the majority of journeys that day will be delayed, this could be true even if the majority of trains are not. Yet we only publically measure train punctuality. Regarding passengers, we have statistics measuring kilometres travelled, the total number of passengers and capacity.

Presumably, there already exists some method of collecting data about the volume of passengers travelling at different times of the day - train operators, Network Rail and others must use such data when planning train timetables and scheduling maintenance. Such data should be made public. There is a push by government, Passenger Focus and the ORR to make more rail data available and make it available in easy to analyse formats, so change is coming on this front.

Overlaying estimated passenger volumes onto train timetables would give an initial, and fairly reliable, idea of how many people were being delayed. Such a move would switch the focus from trains to people.

It's perfectly true that it's easier to accurately measure train punctuality but the current measure underestimates the economic cost of rail delays. This means that train operators, Network Rail and government all make suboptimal investment decisions about rail and related infrastructure projects.

This blog post is not meant as a dig to train operators, Network Rail or any other group. Indeed, any analysis that demonstrates that delays cause higher economic costs than previously thought, might reasonably be used to argue for more funding for rail.

This idea is very simple and I cannot be the first to propose it, although searches via Google and within the ORR and Passenger Focus websites found no reference to the concept. Simple though it is, the idea is compelling. It captures lost economic output and focuses rail network performance on people not rolling stock.