To be 80% below the 2010 estimate seems extreme.
Not considering the economy has been going south since 2008. Many regional airports will be seeing large decreases on the projections for 2008 onwards. For a new airport (the airport was only 3 years old when the economic woes started), the drop will be more extreme. Peel have large pockets, and so DSA will be able to survive the downturn.