NAREIT is the index used to meaure the performance of indirect real east investment.  Some indirect real estate investments have very close correlations with equity markets.  Fore these investments,  the investors can use derivatives of equities to hedge the real estate investment.  So, they are called NAREIT index hedged.  If low(or no) correlatilon exit between the real estate and equities,  the NREIT Index is unhedged. 

If I am wrong, pls correct me！

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