Planning for lateness?

Sir, – Can any of your mathematically minded readers help me out? Latest performance statistics posted in Dart stations show…

Sir, – Can any of your mathematically minded readers help me out? Latest performance statistics posted in Dart stations show almost 100 per cent “Reliability’ and 75 per cent “Punctuality” during a recent month. These terms are defined as Reliability: “ran as planned”; Punctuality: “no later than five minutes” behind schedule.

So almost 100 per cent of Darts trains “ran as planned” but 25 per cent of these were late.

I am confused – were they planned to run late? – Yours, etc,

TONY BURKE,

Abbey Park,

Baldoyle, Dublin 13.