Pupils in Rhondda Cynon Taf missing a 'year of school'
The average pupil in some parts of Wales is missing a year of schooling through poor attendance and truancy, figures suggest.
Rhondda Cynon Taf council has launched a crackdown in an attempt to raise children's standards of achievement.
Its data shows that of the 12 years of statutory schooling, the average pupil only attends classes for 11 years.
Last month, education minister Leighton Andrews said there would be zero tolerance of truancy in future.
The council said if children had good attendance levels they were likely to achieve better exam results.
It added that if children had an attendance rate of 94%, the equivalent of missing 10 days per year, they were more likely to achieve five GCSEs at grade A*-C or equivalent than they would if their attendance was 90%, the equivalent of missing one day a fortnight.
Taking children on a two-week holiday every year in term time means their attendance can be no higher than 94%, the council continued.
Rhondda Cynon Taf council's cabinet member for education, Eudine Hanagan, said: "With the competition for apprenticeships, jobs, college and university places being very high, Rhondda Cynon Taf Council wants to ensure every child is able to compete for a job or training opportunity with any other child across the UK.
"To do so, it is vital that children and young people are given the best education possible. To achieve this, all children need to attend school regularly, with non-attendance being unacceptable.
"If a child is 15 minutes late for school a day, it means the equivalent of losing two weeks of school per year.
"Missing a school day a week is the same as losing a quarter of the year's education."
Ms Hanagan added that "poor attendance and punctuality means bad grades and the effects of it can last a lifetime".
The council said it had improved its attendance and wellbeing service, to support schools to improve attendance in primary and secondary schools.
All schools have been asked to review their school attendance policy and to ensure that parents are fully aware of procedures for reporting absence.
Geraint Davies, of teaching union NASUWT, said parents had a responsibility to combat the problem of truancy.
"In some parts of Wales truancy is on the increase," he said.
"Schools have various processes and procedures to combat truancy, but much of the responsibility is with the parents.
"Taking children out of school during term time for a variety of reasons is also an issue and cumulatively there is an effect on a child's education.
"I'm sure teachers will support the council, but it must have the support of parents to succeed."