Question: What is the net worth of the founder of Open Society Archives as of May 2017?

full_context: Document 1: Open Society Foundations: Open Society Foundations (OSF), formerly the Open Society Institute, is an international grantmaking network founded by business magnate George Soros. Open Society Foundations financially support civil society groups around the world, with a stated aim of advancing justice, education, public health and independent media.
Document 2: Berman Jewish Policy Archive: The Berman Jewish Policy Archive (BJPA), housed at the Graduate School of Education at Stanford University is a centralized electronic database of Jewish communal policy research. Its collection contains more than 20,000 documents, with holdings spanning from 1900 until today. It also is connected to the Jewish Survey Question Bank, a freely available repository of survey tools and questionnaires. The BJPA partners with the North American Jewish Data Bank; together they source the largest publicly available collection of Jewish policy research. The BJPA was established through the Mandell L. and Madeleine H. Berman Foundation, the Charles H. Revson Foundation, and continued with support from the Jim Joseph Foundation.
Document 3: Northwestern University Archives: The Northwestern University Archives, established in 1935, holds thousands of cubic feet of material pertaining to every aspect of the history of its host institution, Northwestern University. The University Archives serves as the repository for both non-current official Northwestern University records and a wide variety of other material including the papers of individual faculty members, the records of student organizations, holdings which pertain to individual students and alumni, photographs, and artifacts. The University Archives' holdings are open for research and reference use and are non-circulating.
Document 4: George Soros: George Soros ( or ; Hungarian: "Soros György" , ] ; born György Schwartz, August 12, 1930) is a Hungarian-American investor, business magnate, philanthropist, and author. Soros is one of the world's most successful investors. As of May 2017, he had a net worth of $25.2 billion, ranking among the 30 richest people in the world.
Document 5: Warren Buffett: Warren Edward Buffett ( ; born August 30, 1930) is an American business magnate, investor, and philanthropist. Buffett serves as the Chief Executive Officer and Chairman of Berkshire Hathaway. He is considered by some to be one of the most successful investors in the world, and as of August 2017 is the second wealthiest person in the United States, and the fourth wealthiest in the world, with a total net worth of $76.9 billion.
Document 6: University on the Square: The University on the Square: Documenting Egypt's 21st Century Revolution is a documentation project by the American University in Cairo (AUC) to collect web content, videos, photographs, personal accounts, oral histories and memorabilia related to the Egyptian Revolution of 2011. The project's objective is to increase public awareness of the Egyptian Revolution and preserve the events of January 25. The memorablia, oral history, photograph, and video collections are composed of AUC community submitted media that are attributed under the Creative Commons Attribution license. Students and faculty may also record testimonials and share their experiences in the revolution. The University on the Square: Documenting Egypt's 21st Century Revolution project is supported by a grant from the Andrew W. Mellon Foundation.
Document 7: Christopher Stone (criminal justice expert): Christopher Stone, an American criminal justice expert, is the President of the Open Society Foundations, the global philanthropies of George Soros. Prior to assuming this position in July 2012, he served as the Guggenheim Professor of the Practice of Criminal Justice at the Harvard Kennedy School from 2005-2012. While at Harvard University, Stone also served as the faculty chair of the Program in Criminal Justice Policy and Management and as the faculty director of the Hauser Center for Nonprofit Organizations. His work at Harvard included research on justice reform in China and Turkey, the development of performance indicators for the justice sector in developing countries, and research on the establishment of the International Criminal Court.
Document 8: Carlos Slim: Carlos Slim Helú (] ; born January 28, 1940) is a Mexican business magnate, investor, and philanthropist. From 2010 to 2013, Slim was ranked as the richest person in the world. He derived his fortune from his extensive holdings in a considerable number of Mexican companies through his conglomerate, Grupo Carso.
Document 9: Michael Bloomberg: Michael Rubens "Mike" Bloomberg (born February 14, 1942) is an American businessman, author, politician, and philanthropist. His net worth is estimated at US$ 53.4 billion, as of July 2017, ranking him as the 6th richest person in the United States and the 10th richest person in the world. He has joined The Giving Pledge, whereby billionaires pledge to give away at least half of their wealth.
Document 10: Open Society Archives: OSA Archivum (abbreviated as OSA, short for Open Society Archives at the Central European University) is an archival repository and laboratory that aims to explore new ways of assessing, contextualizing, presenting, and making use of archival documents both in a professional and a consciously activist way. It was founded by George Soros in 1995.
Document 11: Paul Soros: Paul Soros (Hungarian: "Soros Pál" ; June 5, 1926 – June 15, 2013) was a Hungarian-born American mechanical engineer, inventor, businessman and philanthropist. Soros founded Soros Associates, which designs and develops bulk handling and port facilities. Soros Associates currently operates in ninety-one countries worldwide, as of 2013. Paul Soros was the older brother of George Soros, a successful businessman and financier.
Document 12: Open Society Foundation for South Africa: The Open Society Foundation for South Africa (OSF-SA) is a South African non-profit grant-making organisation that supports the civil society sector. Its mission is to "promote the values, institutions and practices of an open, non-racial and non-sexist, democratic civil society." The foundation was established by George Soros in 1993, just prior to the dismatling of apartheid and South Africa's transition to democracy.
Document 13: Marinko Sudac Collection: The Marinko Sudac Collection, based in Zagreb, Croatia, has been created with a clear collecting strategy based on the region of Central and Eastern Europe, additionally spanning from the Baltic area to the Black Sea. The guiding principle of the Collection is systematic exploration, researching, and promotion of the Avant-Garde practices which have been marginalized, forbidden, and at times completely negated due to the historical, social and political circumstances. In this context, the Marinko Sudac Collection gives the most complete and comprehensive overview on the art of this region. The Collection starts at 1909, and it show the continuity from the first Avant-Gardes, through Neo-Avant-Garde and New Artistic Practices, ending with the fall of the Berlin Wall. The global uniqueness of the Marinko Sudac Collection is also seen in the kind of media it contains. It contains not only traditional artworks, such as paintings, sculptures, and photographs, but it gives equal importance to documentary and archival material. Great importance is put on these almost forgotten media, which enable research of specific phenomena, artists and the socio-political situation which affected this type of art. The Collection contains a great number of museological units, and it treats the documentary and archival material on the same level as traditional artworks. By examining the units contained in the Marinko Sudac Collection, one can read not only the art scene or the art production of a certain artist, but the full status of the society, the socio-political atmosphere of the region in which this art was created in.
Document 14: Li Ka-shing: Sir Ka-shing Li, GBM, KBE, JP (born 29 July 1928 in Chaozhou, China) is a Hong Kong business magnate, investor, and philanthropist. As of September 2017, Li is one of the wealthiest people in Asia, with an estimated net worth of US$34.4 billion. He is currently the chairman of the board for CK Hutchison Holdings; through it, he is the world's leading port investor, developer, and operator, and the largest health and beauty retailer in Asia and Europe.
Document 15: National Security Archive: The National Security Archive is a 501(c)(3) non-governmental, non-profit research and archival institution located on the campus of the George Washington University in Washington, D.C. Founded in 1985 to check rising government secrecy, the National Security Archive is an investigative journalism center, open government advocate, international affairs research institute, and is the largest repository of declassified U.S. documents outside of the federal government. The National Security Archive has spurred the declassification of more than 10 million pages of government documents by being the leading non-profit user of the U.S. Freedom of Information Act (FOIA), filing a total of more than 50,000 FOIA and declassification requests in its nearly 30-year history.
ground_truth: $25.2 billion