The Department for Transport published overall passenger demand forecasts for regional airports on page 130 of its Air Passenger Demand forecasts report:
http://www.dft.gov.uk/pgr/aviation/atf/co2forecasts09/co2forecasts09.pdf
The Government's impact assessment is set out on Her Majesty's Revenue and Customs website and can be accessed via:
http://www.hmrc.gov.uk/ria/apd-reform-ia.pdf