San Francisco's 2012 Proposition C created a long-term source of funding for affordable housing, while capping affordable housing fees (with several notable exceptions) and reducing the inclusionary requirement by 20 percent for those projects that provide their inclusionary units on site. It was also agreed that for those portions of area plans that received a "significant increase" in development potential, the affordable housing fee cap could be lifted. SPUR recommends three thresholds as standards for defining "significant." Applying these standards to future area plans will allow for value recapture where significant residential development potential has been conferred through zoning actions taken by the city.