Denmark uses the krone as its currency and does not use the euro, having negotiated the right to opt out from participation under the Maastricht Treaty of 1992. In 2000, the government held a referendum on introducing the euro, which was defeated with 46.8% voting yes and 53.2% voting no. The Danish krone is part of the ERM II mechanism, so its exchange rate is tied to within 2.25% of the euro. Many political parties in Denmark favour the introduction of the euro and the idea of a second referendum has even been suggested several times since 2000. However, some important parties such as the Danish People's Party, Socialist People's Party and Red–Green Alliance do not support joining the currency. Public opinion surveys have shown fluctuating support for the single currency with majorities in favour for some years after the physical introduction of the currency. However, following the financial crisis of 2008, support began to fall, and in late 2011, support for the euro crashed in light of the escalating European sovereign debt crisis. Denmark borders one eurozone member, Germany, and one EU member that is obliged to adopt the euro in the future but currently has no plans to do so, Sweden. Current Status – ERM II In the ratification process of the Maastricht Treaty in 1992 the Danish government issued a referendum due to constitutional requirements. The Danish constitution requires 5/6 of the parliament's approval in the case of a transfer of sovereignty cf. art. 20 of Grundloven. If this requirement is not met, it will be necessary to host a referendum. The referendum resulted in 50.7% of the population voting against the ratification of the Maastricht Treaty, while only 49.3% voted in favour. The bourgeois coalition government of Denmark in 1992 consisting of Conservatives Agrarian Liberals and the Social democrats held approximately 80% of the seats in the Danish parliament (Folketing) and therefore believed that the referendum would easily get approved which was not the case. The ratification of the Maastricht Treaty needed to be a unanimous decision by all the member states in the EU and the Danish "no" therefore posed a significant issue for the further integration process. Denmark was not the only country issuing a referendum for the ratification of the Maastricht Treaty. In France there was a small majority for the treaty and the Irish population also voted in favour of the ratification