Digital currency destabilizing effect on the Chinese Yuan currency due to speculation. Recent interest in cryptocurrencies has prompted renewed interest in digital currencies, with bitcoin, introduced in 2008, becoming the most widely used and accepted digital currency. According to the European Central Bank's 2015 "Virtual currency schemes – a further analysis" report, virtual currency is a digital representation of value, not issued by a central bank, credit institution or e-money institution, which, in some circumstances, can be used as an alternative to money. In the previous report of October 2012, the virtual currency was defined as a type of unregulated, digital money,
Currency War of 2009–11 a source of contention, concerns over currency war had receded, along with signs that major currencies such as the Renminbi were now much less undervalued than they had been a year previously. Brazil currency had fallen substantially from its peak value against the dollar, allowing Mantega to begin rolling back anti-appreciation measures. In July, the IMF downgraded its assessment of the degree to which the Renminbi is undervalued from "substantially" to "moderately". However, Chinese officials were not pleased, suggesting that their exchange rate is no longer undervalued at all. Whereas in the US, presidential candidate Mitt Romney retains his pledge