Deviation from Purchasing Power Parity (PPP) is real exchange rate?

[Makilab]

Hey everyone,

I'm studying time series topics and I found an example on "real exchange rates". Author says that "deviation from PPP is real exchange rate", but I can't understand the sentence! I put the complete sentence below.

Very regards for answers. 

 

 

"However, at least for advanced economies, deviations from PPP are highly persistent and a substantial body of evidence suggests that the real exchange rates, measuring deviation from PPP, are indistinguishable from non-stationary time series."

[victorydance]

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