We've noted before that when Frances Ryan tells us about some appalling abuse of poverty her numbers never quite add up. There's always a hole where some important digits aren't explained. So it is with this about the expense of schools:

What price can you put on a child’s education? It depends on who that child is. New figures show the average fee for attending a top private school has now risen above £17,000 a year for the first time. In contrast, a child attending a state school in England can expect to have £4,000 to £6,000 spent on them, depending on location and additional allowances. This would be worrying in any circumstances but when we have crumbling and cramped state schools, it feels almost grotesque. While some children enjoy drama halls and swimming pools, others are trying to learn surrounded by leaks, mould and vermin.

Her source is another piece in The Guardian:

Data collected from the 1,300 members of the Independent Schools Council (ISC) – an umbrella body that ranges from famous public schools such as Eton and Harrow to hundreds of smaller prep schools – showed that a child attending a private secondary school as a day pupil would cost around £15,000 a year, while a boarder would pay £33,000.

The figures showed an increase of 3.3% compared with 2017, which the ISC said was the slowest annual rate of increase since 1994. However, independent school fees have outstripped the rate of inflation over that period.

The average annual fee for a day pupil was around £13,000 three years ago but 10 years ago the same education cost £9,600 a year. Boarding fees have risen by 50% in the last 10 years, having cost on average £22,000 in 2008.

In comparison, state schools in England receive around £4,000 to £6,000 per pupil depending on location and additional allowances for language and disadvantage, as well as access to funds for buildings and maintenance.

That last clause is really rather important, don't you think? Especially as Ryan's complaint above is about the physical estate of the state sector.

The private school number includes both the operating costs of that school and also the capital - and maintenance - costs of the school estate. The numbers for the state school are instead only the operating costs, not including those maintenance nor capital costs.

From memory we'd also suggest that the private school numbers include the substantial pensions costs of the teaching staff, the state ones not. But that is from memory, we're not stating it as a fact.

When one Guardian article doesn't even manage to pick up the correct numbers from another Guardian article - that's why we don't actually believe any numbers in The Guardian, ever.