Teachers at Dutch primary schools are getting older and one in five now is over the age of 55, national statistics agency CBS said on Wednesday.

That means the number of teachers some 10 years away from retirement has almost doubled in the past 14 years. Men dominate the ranks of older teachers – one in three male primary school teachers is over the age of 55.

At the same time, the number of students at teacher training colleges has slumped, the CBS said. In the 2003/04 academic year, 10,000 people were attending pabo colleges to become a teacher. There are just 4,500 students in the current academic year.

The CBS says the sharp drop is due to stronger selection procedures to become a teacher.

Dutch primary schools have been hit by a series of strikes in recent months as teachers call for better pay and measures to ease the pressure of work, partly due to the shortage of staff.

Although school pupil numbers will decline in the years to come, there is a mismatch with teacher numbers and the teacher shortage will increase, the CBS said.