Question: When was Greece accepted into the union where the basic MP3 decoding and technology is patent free?

full_context: Document 1: MP3: An exception is the United States, where patents filed prior to 8 June 1995 expire 17 years after the publication date of the patent, but application extensions make it possible for a patent to issue much later than normally expected (see submarine patents). The various MP3-related patents expire on dates ranging from 2007 to 2017 in the U.S. Patents filed for anything disclosed in ISO CD 11172 a year or more after its publication are questionable. If only the known MP3 patents filed by December 1992 are considered, then MP3 decoding has been patent-free in the US since 22 September 2015 when U.S. Patent 5,812,672 expired which had a PCT filing in October 1992. If the longest-running patent mentioned in the aforementioned references is taken as a measure, then the MP3 technology will be patent-free in the United States on 30 December 2017 when U.S. Patent 5,703,999, held by the Fraunhofer-Gesellschaft and administered by Technicolor, expires.
Document 2: MP3: The basic MP3 decoding and encoding technology is patent-free in the European Union, all patents having expired there. In the United States, the technology will be substantially patent-free on 31 December 2017 (see below). The majority of MP3 patents expired in the US between 2007 and 2015.
Document 3: MP3: Sisvel S.p.A. and its U.S. subsidiary Audio MPEG, Inc. previously sued Thomson for patent infringement on MP3 technology, but those disputes were resolved in November 2005 with Sisvel granting Thomson a license to their patents. Motorola followed soon after, and signed with Sisvel to license MP3-related patents in December 2005. Except for three patents, the US patents administered by Sisvel had all expired in 2015, however (the exceptions are: U.S. Patent 5,878,080, expires February 2017, U.S. Patent 5,850,456, expires February 2017 and U.S. Patent 5,960,037, expires 9. April 2017.
Document 4: Greece: Greece is a democratic and developed country with an advanced high-income economy, a high quality of life and a very high standard of living. A founding member of the United Nations, Greece was the tenth member to join the European Communities (precursor to the European Union) and has been part of the Eurozone since 2001. It is also a member of numerous other international institutions, including the Council of Europe, NATO,[a] OECD, OIF, OSCE and the WTO. Greece, which is one of the world's largest shipping powers, middle powers and top tourist destinations, has the largest economy in the Balkans, where it is an important regional investor.
Document 5: MP3: Technicolor (formerly called Thomson Consumer Electronics) claims to control MP3 licensing of the Layer 3 patents in many countries, including the United States, Japan, Canada and EU countries. Technicolor has been actively enforcing these patents.
Document 6: MP3: In September 1998, the Fraunhofer Institute sent a letter to several developers of MP3 software stating that a license was required to "distribute and/or sell decoders and/or encoders". The letter claimed that unlicensed products "infringe the patent rights of Fraunhofer and Thomson. To make, sell and/or distribute products using the [MPEG Layer-3] standard and thus our patents, you need to obtain a license under these patents from us."
Document 7: MP3: Other lossy formats exist. Among these, mp3PRO, AAC, and MP2 are all members of the same technological family as MP3 and depend on roughly similar psychoacoustic models. The Fraunhofer Gesellschaft owns many of the basic patents underlying these formats as well, with others held by Dolby Labs, Sony, Thomson Consumer Electronics, and AT&T.
Document 8: Economy of Greece: Between 1832 and 2002 the currency of Greece was the drachma. After signing the Maastricht Treaty, Greece applied to join the eurozone. The two main convergence criteria were a maximum budget deficit of 3% of GDP and a declining public debt if it stood above 60% of GDP. Greece met the criteria as shown in its 1999 annual public account. On 1 January 2001, Greece joined the eurozone, with the adoption of the euro at the fixed exchange rate ₯340.75 to €1. However, in 2001 the euro only existed electronically, so the physical exchange from drachma to euro only took place on 1 January 2002. This was followed by a ten-year period for eligible exchange of drachma to euro, which ended on 1 March 2012.
Document 9: Cyprus: According to the latest International Monetary Fund estimates, its per capita GDP (adjusted for purchasing power) at $30,769 is just above the average of the European Union.[citation needed] Cyprus has been sought as a base for several offshore businesses for its low tax rates. Tourism, financial services and shipping are significant parts of the economy. Economic policy of the Cyprus government has focused on meeting the criteria for admission to the European Union. The Cypriot government adopted the euro as the national currency on 1 January 2008.
Document 10: MP3: The initial near-complete MPEG-1 standard (parts 1, 2 and 3) was publicly available on 6 December 1991 as ISO CD 11172. In most countries, patents cannot be filed after prior art has been made public, and patents expire 20 years after the initial filing date, which can be up to 12 months later for filings in other countries. As a result, patents required to implement MP3 expired in most countries by December 2012, 21 years after the publication of ISO CD 11172.
Document 11: Estonia: As a member of the European Union, Estonia is considered a high-income economy by the World Bank. The GDP (PPP) per capita of the country, a good indicator of wealth, was in 2015 $28,781 according to the IMF, between that of Slovak Republic and Lithuania, but below that of other long-time EU members such as Italy or Spain. The country is ranked 8th in the 2015 Index of Economic Freedom, and the 4th freest economy in Europe. Because of its rapid growth, Estonia has often been described as a Baltic Tiger beside Lithuania and Latvia. Beginning 1 January 2011, Estonia adopted the euro and became the 17th eurozone member state.
Document 12: Greece: The Greek economy is classified as advanced and high-income. Greece was a founding member of the Organisation for Economic Co-operation and Development (OECD) and the Organization of the Black Sea Economic Cooperation (BSEC). In 1979 the accession of the country in the European Communities and the single market was signed, and the process was completed in 1982. Greece was accepted into the Economic and Monetary Union of the European Union on 19 June 2000, and in January 2001 adopted the Euro as its currency, replacing the Greek drachma at an exchange rate of 340.75 drachma to the Euro. Greece is also a member of the International Monetary Fund and the World Trade Organization, and is ranked 24th on the KOF Globalization Index for 2013.
Document 13: Greece: Greece is a developed country with high standards of living[citation needed] and high Human Development Index. Its economy mainly comprises the service sector (85.0%) and industry (12.0%), while agriculture makes up 3.0% of the national economic output. Important Greek industries include tourism (with 14.9 million international tourists in 2009, it is ranked as the 7th most visited country in the European Union and 16th in the world by the United Nations World Tourism Organization) and merchant shipping (at 16.2% of the world's total capacity, the Greek merchant marine is the largest in the world), while the country is also a considerable agricultural producer (including fisheries) within the union.
Document 14: Economy of Greece: Greece is classified as an advanced, high-income economy, and was a founding member of the Organisation for Economic Co-operation and Development (OECD) and of the Organization of the Black Sea Economic Cooperation (BSEC). The country joined what is now the European Union in 1981. In 2001 Greece adopted the euro as its currency, replacing the Greek drachma at an exchange rate of 340.75 drachmae per euro. Greece is a member of the International Monetary Fund and of the World Trade Organization, and ranked 34th on Ernst & Young's Globalization Index 2011.
Document 15: Economy of Greece: Greece is a developed country with an economy based on the service (82.8%) and industrial sectors (13.3%). The agricultural sector contributed 3.9% of national economic output in 2015. Important Greek industries include tourism and shipping. With 18 million international tourists in 2013, Greece was the 7th most visited country in the European Union and 16th in the world. The Greek Merchant Navy is the largest in the world, with Greek-owned vessels accounting for 15% of global deadweight tonnage as of 2013. The increased demand for international maritime transportation between Greece and Asia has resulted in unprecedented investment in the shipping industry.
ground_truth: 19 June 2000
sub_queries: Where is the basic MP3 decoding and technology patent free? Answer: European Union
When was Greece accepted into European Union ? Answer: 19 June 2000