REITs will have to make changes as the shift to global accounting standards accelerates, says Serena Wolfe, senior manager of Ernst & Young's Global Real Estate Center. Under U.S. GAAP standards, firms typically report their real estate investments at cost, depreciating over the useful life of the asset. If U.S. firms move to the International Financial Reporting Standards, they will have to mark assets to fair value at each reporting period. "There will no longer be a gradual decline in value due to depreciation. There will now be swings up or down depending on where you are in the economic cycle," Wolfe said.