If residents can afford to stay, they are better off.

Some can’t, and have to relocate. Housing prices go up, which increases the wealth of homeowners in the area. But taxes increase also, which may force some of them to sell-out.

The study says that cities will do well to have proactive policies.

“Preserving and expanding the affordability and accessibility of central urban neighborhoods should primarily take a forward-looking approach that seeks to accommodate increasing demand for these areas. A growing recent literature suggests that building more housing (whether market-rate or affordable) is a promising way of maintaining and expanding housing affordability.”

The Atlanta Journal-Constitution took a long look in May at the changes gentrification is bringing to people who live in the city's Old Fourth Ward.

The fastest-gentrifying cities in the U.S. from 2000-2014.

1. Washington

2. Portland

3. Seattle

4. Atlanta

5. Denver

6. Charleston

7. Austin

8. Boston

9. Raleigh

10 Richmond