The loss of staff during training and in their first few years at work is a common problem facing many employers, especially when the economy is buoyant and jobs are plentiful.
It is difficult to piece together whether this is a real issue for teaching as not all the information required is easily obtainable.
For the past few years, the Department for Education and Employment has stopped publishing details of new entrants to secondary teaching by subject, and details of those leaving aren't generally available either on a subject-by-subject basis.
However, it is now possible to look at what has happened to PGCE students from the 1995-96 academic year during their first few years in the profession. For example, of the 940 history PGCE students who entered training that year only 780 went into teaching in September 1996.
Threeyears later the number still in teaching, according to the DFEE, was down to about 660, or around 85 per cent of those who had entered directly from their PGCE.
In general, history teachers seem to have been leaving at between 5 and 6 per cent a year during their first three years. However, their number is likely to be topped up by some "late entrants" who delayed starting their teaching careers or didn't immediately find a teaching post.
If the rate of history teachers leaving drops after the first few years, as the remaining graduates settle into their careers, this relatively low rate of early "wastage" is of little concern, since history is a subject with adequate levels of recruitment.
However, in subjects such as maths, where recruitment targets have been missed in many years, even such a low rate of departure would be worrying.
John Howson is managing director of Education Data Surveys Int.email@example.com