When we last wrote about the follow-up probationer survey by the General Teaching Council for Scotland, exactly a year ago, we began: “Lies, damned lies and statistics.” Plus ca change. The Government inevitably homes in on the fact that “86.4 per cent of teachers are in work”, whether that is permanent, temporary or supply - an increase of 13.9 per cent since the start of the school year. Labour concentrates on the 10 per cent drop in the number of 2008-09 probationers who had obtained permanent posts by April 2010.

The triple whammy of the economic crisis, the absence of teaching jobs and the local government concordat which removed ministers’ ring-fenced powers, has combined to make a bad situation worse. The Education Secretary has been doing his best, rushing around to shore up as many dykes as he can. He has had to reduce the numbers in training - very reminiscent of the crisis in the mid-1970s when the International Monetary Fund had to bail out Britain, forcing cutbacks in the then colleges of education. And he has done his bit by agreeing to smaller decreases in class sizes than he would wish, to create some demand for more teachers.

Yet it is the trend that matters, and it is unmistakable. The last three GTCS April surveys have shown an increase in the number of probationers on supply work, from 12.7 per cent to 19.6 per cent to 26.5 per cent - a growing “casualisation” of the workforce, as Labour is right to point out. At the same time, the number gaining permanent posts has declined from 51.3 per cent to 39.5 per cent to 30 per cent.

The final word of statistical caution is that the GTCS survey does not reveal the true extent of the problem, since only 1,249 probationers out of a possible 3,013 responded. The fate of the others is therefore unknown.

Neil Munro, editor of the year (business and professional magazine).