Funding per student in school sixth forms has fallen by 21% since its peak in 2010-11, according to analysis by the Institute for Fiscal Studies.
The IFS said that the “severe squeeze” on school spending, which has seen spending per pupil fall by 8% between 2009-10 and 2017-18, has been driven by a 55% cut to local authority spending on services.
The report, out today, which was funded by charitable trust the Nuffield Foundation, said that school sixth forms have borne the brunt of budget cuts at 21% per student while further education and sixth-form college funding per student has fallen by about 8% since 2010-11.
By 2019-20, funding per young person in further education will be at about the same level as in 2006-7 - only 10% higher than it was thirty years earlier in 1989-90, according to the IFS.
Total funding for adult education and apprenticeships has fallen by 45% since 2009-10.
Tim Gardham, chief executive of the Nuffield Foundation, said: “The fall in further education spending is clear and worrying.
“The IFS analysis questions the capacity of the system to successfully deliver the reforms currently underway without additional funding.
“Neglect in investment in one educational stage has knock-on effects for others, from the point of view of the individual student and the education system as a whole.”
Research by the think-tank also showed a large increase in spending on early years education - spending on three- and four-year-old entitlement to early education - has risen from “almost nothing” in early 1990s to around £3bn in 2017-18.
But, early years spending in other areas fallen, including a 13% drop in childcare subsidies between 2009-10 and 2017-18 and a 67% reduction in spending on children’s Sure Start centres.
Christine Farquharson, co-author of the IFS report, said: “Recent changes to funding formulas in early years, schools and the further education system introduce a more transparent way of allocating resources between institutions and around the country.
“However, the next big challenge across all these stages is to work out how to design systems that encourage childcare settings, schools, colleges and universities to deliver high-quality education.”
A Department for Education spokesperson said: “Whilst we accept that there are pressures across the system we have protected base rate funding for 16 to 19 year olds until 2020, and are putting more money into our schools than ever before.
“We understand the pressures in further education, which is why our wide ranging review of post-18 education and finding is looking at how the system can work better for everyone, ensuring value for money for students and taxpayers.”
The Public Accounts Committee recently found that budget cuts threatened to undermine Ofsted’s effectiveness.
Earlier this month the Local Government Association warned that 134,000 children could miss out on a school place by 2023-24.
