Sustainability index aims to evaluate REITs on the greenness of their properties

FTSE Group, the National Association of Real Estate Investment Trusts, and the U.S. Green Building Council are working on a sustainability index that measures the portfolios of real estate investment trusts to provide transparency about LEED certification and Energy Star ratings. Scheduled to launch on March 21, the green-property index will feature the same set of real estate investment trusts, or REITs, thatcomprisean existing benchmarkfor U.S. real estate. Each of 172 companies will receive a score based on the proportional value of their holdings that have achieved LEED certification or Energy Star labeling.

(http://www.greenbiz.com/news/2013/03/07/sustainability-ratings-real-estate-investments)