Great Western Coffee Shop

There's never been an obvious measure that I've seen to compare the effect of service cancellations  on passengers. Which is a shame, because passenger trains are provided (or are supposed to be) for the people who use them - or could use them - and who live near the stations. 

I remember a web site someehere to the south of where I live that use to shout that trains were cancelled for OPERATIONAL CONVENIENCE ... and clearly there is no measure there.   

So what have I tried?
* The population within the station catchment area multipled it by
* The percentage of short notice cancellations over the past 12 weeks and multiplied that by
* The average daytime interval between trains in the most frequent direction

So for example - Frome -
Catchment area population   - 25000
Average gap between trains in the same direction on the major service - 50
Cancellation Rate - 3 (percent)
Multiply together - 3,750,000 - and the lower the figure, the better

Trowbridge:
Average gap between trains in the same direction on the major service - 20
Cancellation Rate - 3 (percent)
Catchment area population   - 40000
Multiply together - 2,400,000

Salisbury:
Average gap between trains in the same direction on the major service - 30
Cancellation Rate - 2 (percent)
Catchment area population   - 45000
Multiply together - 2,700,000

Tisbury:
Average gap between trains in the same direction on the major service - 60
Cancellation Rate - 1 (percent)
Catchment area population   - 2500
Multiply together - 150,000

This is clearly not going to work particularly well for stations which are primarily destinations - the population of Looe, for example, is low and catchment is a poor choice.  Similarly, where stations are predomianty city stations with long distance traffic and rail does not form so much of a short distance facility such as Plymouth they will be outside this symplistic envelope - but what do others think of the methodology before I share other figure in our area?