THE number of young teachers in classrooms is falling with statistics showing almost half are out of work.
Older staff staying on for longer and limited job openings are among the reasons being offered for an ageing profession.
Only about one in 10 teachers in employment are aged 30 and under, while the proportion of those aged 65 remaining registered is on the rise.
It is hoped a multi-million pound drive to replace hundreds of near-retirement age teachers with younger staff will help reverse the decline.
The General Teaching Council publishes an annual digest of statistics, which details the number of teachers by gender and age. It also shows how many are working as well as those who are registered but out of work.
There were 3,926 teachers under the age of 30 on the register at March last year - of which just 2,135 had jobs.
The proportion of 24-29-year-olds on the register fell for the fourth year in row - it was 14.7 per cent, down from 16.1 in 2013.
At the same time, the proportion staying on beyond 65 has been increasing, although the actual numbers are small.
The median age of teachers was 41.5 years, an increase from 41.0 in 2013.
It is hoped the executive's Investing in the Teaching Workforce Scheme will boost the number of young staff in work.
It was intended that up to 500 recently qualified graduates would replace those willing to retire early.
In 2018/19, the scheme will release up to 200 older teachers.
Justin McCamphill from the NASUWT union said he expected to see an increase in younger teachers.
"Part of the reason is the ageing workforce because of changes to retirement and the decline in wages in real terms. It means these people are working longer," Mr McCamphill said.
"The Investing in the Teaching Workforce scheme should create significant job opportunities for people under 30 who qualify and we should see a different picture.
"But in the longer term, something has to be done to address the adverse impact of changes to the state pension, which will see people working until they are 67."
Separate Department of Education statistics, meanwhile, reveal the number of substitution days being worked by prematurely retired teachers has plummeted in recent years.
It fell to 6,305 days in 2017/18 - just 1.3 per cent of the total days worked - compared to 14.4 per cent in 2008/09.
This is largely due to changes in pay for substitute teachers. Since 2011, anyone who has retired but is then re-employed is put back to point one on the pay scale.
