90% of trains are on time

According to Network Rail's latest news release, "An average of 89.5% of trains ran on time over the first six periods of the year [2006]".
Does this mean I only have to pay 89.5% of the fare? No. I'm still left paying 100% of the fare of 89.5% of the service.
I'm considering coming into work for 80% of the time I currently work. Do I expect to have 100% of the pay? No, I expect 80% of the pay.
Would the bank be happy if I paid 89.5% of my mortgage?
What if I only got 89.5% of a sandwich?

When will the fat controllers stop running the trains as if they're running for the sake of running, and start to realise that they're running because people want to travel on them?