Difficult to keep track of train operators' profits

The debate over whether the next government should renationalise the railways has continued across several media outlets this week.

In a letter to the Times this morning, the Chairman of the Rail Delivery Group, Martin Griffiths, laid out what he saw as the facts against a change in policy.

Among them, he claimed the private sector doesn't siphon off large profits, and in fact operating margins were on average about 3%, dwarfed by the money the government gets from the train operating companies.

The 3% figure is from last year: train operators brought in, on average, £16 million more than they paid in expenditure: the equivalent of a 3.4% margin. Previous analysis by KPMG shows this level has been roughly the same for the past decade. The latest figures show it's now lower at 1.7%.

But operating margins aren't profits, as the Office for Regulation makes clear. It doesn't take into account tax deductions during accounting, for instance.

The House of Commons Library has previously analysed actual profits, which show that in reality the picture varies massively across different train operating companies. In 2011, South West Trains made a £47.5 million profit, while Chiltern Railways actually made a £57 million loss.