Wilshire Associates introduced the Wilshire US Real Estate Securities Index (RESI) in September 1991. Our purpose was to create an index of publicly traded real estate equity securities without the limitations of other appraisal based indexes.  In addition, the Wilshire US RESI was developed to offer a market based index that is more reflective of real estate held by pension funds.

The Wilshire US Real Estate Investment Trust (REIT) Index and the Wilshire US Real Estate Operating Companies (REOC) Index are subsets of the Wilshire US RESI.

In 2006, Wilshire released the Wilshire Global Real Estate Securities Indexes as an expansion of the original U.S. real estate indexes to serve as a proxy for direct real estate investments by institutions.