Editing Purchasing power parity (section)

===Identifying manipulation===

PPP exchange rates are especially useful when official exchange rates are artificially manipulated by governments. Countries with strong government control of the economy sometimes enforce official exchange rates that make their own currency artificially strong. By contrast, the currency's black market exchange rate is artificially weak. In such cases, a PPP exchange rate is likely the most realistic basis for economic comparison. Similarly, when exchange rates deviate significantly from their long term equilibrium due to speculative attacks or carry trade, a PPP exchange rate offers a better alternative for comparison.

In 2011, the [[Big Mac Index]] was used to [[Big Mac Index#Manipulation|identify manipulation of inflation numbers by Argentina]].<ref>{{Cite web|url=https://latitude.blogs.nytimes.com/2011/11/24/argentinas-big-mac-attack/|title=Argentina's Big Mac Attack|last=Politi|first=Daniel|date=2011-11-24|website=Latitude|language=en-US|access-date=2019-10-23|archive-url=https://web.archive.org/web/20191023175605/https://latitude.blogs.nytimes.com/2011/11/24/argentinas-big-mac-attack/|archive-date=2019-10-23|url-status=dead}}</ref>