For landowners with little income subject to state taxation, a tax credit is a hollow reward for reducing the value of real property by donating a conservation easement. To respond to this, Colorado conservationists made their state tax credit transferable in 2000—that is, the donor/landowner can sell her/his credit to other parties; the buyers then use the purchased tax credit to pay their Colorado income tax. This is appealing to buyers because the credit is sold at a discount from face value. Virginia followed by enacting transferability in 2002. Delegate Bill Howell (now Speaker of the Virginia House of Delegates) introduced HB1322, which had been suggested to him by conservationists Charles Davenport and Phil Hocker. HB1322 was enacted, effective retroactively to January 1, 2002. Other states have followed since. However, "caps" on the amount of credit an easement can generate, and other restrictions, limit the scope of the different state tax credit programs in varying manners.