The Department recently published an assessment of trends in the level of teachers’ pay in our evidence to the School Teachers' Review Body (STRB), available at: https://www.gov.uk/government/publications/evidence-to-the-strb-2018-pay-award-for-school-staff.
Statutory terms and conditions for teachers in maintained schools in England and Wales are set out in the School Teachers' Pay and Conditions Document (STPCD). Non-maintained schools are responsible for determining staff pay and conditions themselves.
If a supply teacher is employed by a private agency, this is a private commercial arrangement between the school and the agency.
The Teachers’ Pension Scheme (TPS) undertakes a comprehensive analysis every four years as part of the scheme valuation. The latest valuation is available at: https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/324305/TPS_2012_valuation_report_FINAL_9_June_2014.pdf.
A further report will be published later this year. As teachers employed through supply agencies are not eligible to participate in the TPS, there is no data available.