'One-in-12 teachers quit each year'
The number of teachers quitting the profession has reached a ten-year high, according to official figures.
Almost 50,000 left the classroom in a 12 month period in 2012/13.
The figures come just days after a poll found that the majority of trainee and newly-qualified teachers have already considered leaving, and are likely to spark fresh concerns about workload and pressures on school staff.
Overall, around one in 12 full-time teachers are leaving teaching each year, according to an analysis of government data by the Times Educational Supplement (TES).
The Department for Education's statistics show that 49,373 qualified teachers left state schools in the 12 months up to November 13 - the latest figures available.
The previous year, up to November 2012, that figure was 48,843.
A decade ago, in the financial year 2004/5, 41,880 teachers quit the classroom.
The Department for Education (DfE) insisted that teaching is still a "hugely popular career" with record levels of top graduates joining the profession.
The figures also show that in the same period up to November 2013, there were 53,329 entrants to teaching, compared to 50,906 this year before.
Christine Blower, general secretary of the National Union of Teachers (NUT) told the TES: "It is no surprise that teachers are voting with their feet.
"A combination of unacceptable number of hours worked, a punitive accountability system, the introduction of performance related pay and being expected to work until 68 for a pension has turned teaching into a less than attractive career choice."
A recent poll conducted by the Association of Teachers and Lecturers (ATL) revealed that t hree in four trainee and newly-qualified teachers have already considered leaving the profession.
The top reason given for wanting to quit was workload.
More than half of those surveyed said that they do not think they will still be in teaching in 10 years time, while one in four thought they would be out of the classroom in just five.
Last autumn, the Government pledged to look at teacher workload, with Education Secretary Nicky Morgan and Deputy Prime Minister Nick Clegg launching the Workload Challenge.
The ministers called on school staff to submit examples of the unnecessary paperwork and administration they are being asked to complete which they think should be scrapped or cut back.
Tens of thousands of teachers responded to the call.
A DfE spokesman said: "Teaching continues to be a hugely popular career with more teachers in England's classrooms than ever before and record levels of top graduates entering the profession.
"Not only do these figures show the proportion of teachers joining the profession has risen - now 53,000 a year, but those teachers leaving have remained low, with over three quarters still in the profession after five years of service."
In his annual report last month, Ofsted boss Sir Michael Wilshaw warned that teacher recruitment is a pressing issue, with not enough new staff joining the profession and good entrants not always going to the schools where they are most needed.
Figures show that the number of entrants into teacher training has fallen by 17% since 2009/10 and was 7% below the number of places needed in 2014/15, Sir Michael's report noted - adding that the numbers of secondary trainees have seen the largest falls with ''persistent problems'' in key secondary subjects such as maths and physics.