But the spread of finance has not been equal with only£500m financing school projects compared with£6bn for transport.
PFI involves a private sector consortium, made up of usually a contractor, a financier and an operator, signing a long-term contract to build, fund and operate a public building.
In return a local authority or government department agrees to rent the building and pay an annual fee to the consortium.
A consortium including Tarmac, BT, Group 4 and Deutsche Bank have signed a£300m 30-year contract to build the new Government Communications Headquarters (GCHQ).
The base, dubbed the 'doughnut' because of its shape, will be either built at the existing GCHQ base near Cheltenham or a proposed site at Gloucester.