In the last twelve months, the argentine peso (ARS) lost about 11% of its value in comparison to USD.
In the same time range the prices rouse about 29% (spanish).
What's the reason for this effect? I am living in Argentina for about 2 years, and the prices even feel worse to the published statistics. The government is acting very "special": it's starting social programs one after another and is building lots of (unneeded, or at least oversized) infrastructure using money with unclear origin (well, a lot of this money is draining in similar circumstances, too).
So, who is willing to pay this price for Pesos, since they do not have any value outside of argentina? In my expectation the demand for Pesos is really low, and since Argentina maintains a trade deficit, it is forced to import lots of goods, payed with Dollars. They should have a pressing demand for Dollars. And economics say: low demand + great offer = low price.