The Peruvian nuevo sol has maintained a relatively stable exchange rate between 3.6 and 3.0 with respect to the US dollar for the period 2000-2007.
Between December 2007 and September 2008 the exchange rate fell below 3.0 nuevos soles per 1 USD, a rate not seen since 1997. As of October 2008 the nuevo sol started to depreciate again, passing the 3.0 mark. Since May 2009 the nuevo sol has been falling again.
Source: Banco Central de Reserva del Perú
See also: Historical exchange rates for multiple currencies