Private equity investment presupposes a revenue stream from which the private investor can earn a return. The revenue stream, however, does not have to consist of an interest in tolls or other fees imposed directly on users of the project. Great Britain has used "shadow tolling" support their PFI program. Today, the Florida Department of Transportation, in the first procurement of its kind in the United States, is offering annual "availability payments" to prospective concessionaires willing to build, own and operate a new non-tolled tunnel to the Port of Miami. Payments will be made directly to the concessionaire by FDOT based on hours of lane availability of and such other factors as safety and compliance with operating and maintenance standards.