The International Monetary Fund will use estimates from private sector and provincial governments to measure economic growth and inflation in Argentina.
President Cristina Fernandez de Kirchner has been insisting that her government's data is reliable, but the IMF doesn't seem to be buying it.
Until "the quality of data reporting has improved, IMF staff will also use alternative measures of GDP growth and inflation for macroeconomic surveillance...," the IMF said, according to Dow Jones Newswires.
Argentina's national statistics agency said inflation was running at almost 10 percent in August, while private sector estimates put the number at more than 20 percent.
The agency's data has been questioned ever since former President Nestor Kirchner replaced its civil servants with political appointees in 2007.
The IMF forecast Argentina's economic growth at 8 percent this year, and 4.6 percent in 2012.
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