The Colombian government said Wednesday that it purchased an additional 500 million U.S. dollars in the past week to stop the revaluation of the Colombian peso versus the dollar. "So far, we have bought 500 million dollars," Colombian Finance Minister Juan Carlos Echeverry told a press conference in Bogota on the government's measures to prevent the peso's appreciation. "We are going to be watching the market's behavior so that ... in addition to the actions the Bank of the Republic (Colombia's central bank) is taking, we can see to the exchange rate," Echeverry said. The Colombian peso has appreciated 8.1 percent in 2012, and the government's latest step knocked the rate down to 6.5 percent. Since the beginning of August, Colombia's central bank has been buying 20 million dollars daily, as part of a program that will last until November and is expected to stop the impact of the currency's appreciation and its effect on businesses and the general public.