Case study on Tifton, Georgia on the impact of historic preservation on local economies in Georgia –
http://www.athensclarkecounty.com/~planningdept/hpecon3.html

Here is the conclusion:
“The citizens of Tifton have made a strong commitment to preserving their community's historic character. Programs such as Main Street have helped to revitalize the downtown area, while local residents take pride in their historic neighborhoods. The information compiled using the National Trust methodology reflects this outlook.
Tourism, construction, and real estate activities analyzed in this study were shown to have a positive impact on the Tifton community. Statistics indicate that tourism is a growing industry in the region. Construction data shows that designated residential neighborhoods contributed double the jobs and twice as many dollars to the local economy when compared to non-designated areas. Analysis of real estate figures confirms preservation's contributions. The property tax values in designated areas were shown to increase at the same rate as those in non-designated neighborhoods. Since obtaining local designation in 1988, property values in the downtown area have appreciated at a rate greater than the other areas. Overall, the data supports the designation of historic areas as a means of maintaining economic viability. The success of the Myon Complex renovation represents the community's confidence in preservation as a form of progress.”