January used to herald an eagerly awaited event on the Welsh education calendar: the publication of figures showing the per-pupil funding gap between Wales and England.
There was widespread shock in 2009 when the gulf was revealed to be almost #163;500 per pupil, with Wales on the losing end of the equation. By 2011 it had hit #163;604, leaving the Welsh government facing accusations that it was underfunding schools. But last January statisticians said the figure could no longer be published, blaming changes to the "education policy landscape" in England, including the rise in the number of academies.
Education minister Leighton Andrews claimed to be "profoundly disappointed" by the news and instructed his officials to look into the matter again. But almost a year on, they are no closer to a breakthrough and the annual update due for later this month has been cancelled.
Teaching unions are angry about the lack of information. They have spent much of the past decade campaigning for greater transparency and an end to the so-called "funding fog" around education.
"Ever since devolution, education has been underfunded," said Rex Phillips, Wales organiser of the NASUWT. "It is an issue no education minister has ever got to grips with.
"If schools are not properly funded they are not going to succeed, it's as simple as that. What the current minister has tried to do is shift the focus from underfunding to underachievement. We still want to see the figure. It should not be beyond the will and wit of the Welsh government to produce it."
Philip Dixon, director of ATL Cymru, said that Welsh schools suffered from "chronic underfunding".
"The current minister has made some progress, but the long-term damage done by his predecessors, who let the gap grow from nothing to over #163;600, will not be easily undone," he said.
However, one of the chief agitators on the issue has had a recent change of heart. For many years David Reynolds, a professor of education at Plymouth and later Southampton universities, publicly highlighted the funding gap and criticised the government for underspending on Welsh pupils, often on the pages of TES.
But, now working as a senior policy adviser to the Welsh government, Professor Reynolds says that funding is "not such a big deal". His opinion has been shaped by the publication of the 2009 Pisa (Programme for International Student Assessment) results two years ago.
"Pisa showed quite clearly that some high-spending countries get nowhere and some low-spending countries get some good results," said Professor Reynolds. "I wonder now whether it's as big an issue as I once thought.
"It appears that because of the changing nature of the English education system, with the academies programme and growing central funding of schools, coupled with the changing qualifications landscape, it's going to be increasingly difficult to compare the two countries."
Professor Reynolds said extra funding would make little difference to Wales' education problems because many were "deep-rooted" in culture and history. "I firmly believe that if you gave every school in Wales 10 per cent extra funding, there wouldn't be any more than a flicker of improvement," he said.
The Welsh government said it was still committed to trying to work out the funding gap. "Government statisticians are in regular dialogue with Department for Education statisticians to try to tackle this issue," a spokeswoman said. "The issues outlined in the January statistical article are still relevant and the impact of the academy programme continues to make comparisons difficult."