The most generous people of 2013

The Chronicle of Philanthropy has released its annual ranking of the most generous donors of 2013, and Mark Zuckerberg and his wife Priscilla Chan have again topped the list with a donation of almost a billion dollars. Last year's top 50 givers donated US$7.7 billion in 2013, a 4 per cent increase from 2012. See the full list in our gallery.

Amount donated in 2013: US$992.2 million Beneficiary: Silicon Valley Community Foundation The Facebook co-founder and his wife, a paediatrician, made the record-breaking gift of 18 million shares of Facebook stock in December. It's not their first huge gift: in 2012, the couple donated the same number of shares to the foundation, valued at around US$500 million. Zuckerberg, 29, and Chan, 28, are the youngest donors on the list: the median age of the top 50 givers was 72.

Amount donated in 2013: Approximately US$750 million Beneficiary: Cynthia and George Mitchell Foundation The fracking pioneer was the founder of Mitchell Energy and Development, a gas and oil company in Texas, which he sold for approximately US$3 billion in 2002. He passed away in July at the age of 94, leaving the large bequest to the Cynthia and George Mitchell Foundation, which he and his late wife established in 1978. Its currently supports lean energy, natural-gas sustainability, science and water.

Amount donated in 2013: US$500 million Beneficiary: Oregon Health & Science University Foundation Nike co-founder and chairman Phil Knight made waves last year when he announced that he and his wife would donate half a billion dollars in support of cancer research, on the condition that OHSU officials would raise the same amount in two years.

Amount donated in 2013: US$452 million Beneficiaries: Arts, education, environment, and public-health groups, and programmes aimed at improving city governments around the world A report by the New York Times also revealed that the founder of Bloomberg spent about US$650 million of his own fortune on New York City during his three terms as mayor.

Amount donated in 2013: US$296.2 million Top beneficiary: Laura and John Arnold Foundation Other notable gift: Fidelity Charitable Gift Fund John Arnold, founder of hedge fund Centaurus Energy, and his wife Laura, a former corporate lawyer, have put more than US$1 billion into their charitable foundation since they established it in 2008. Last year it awarded US$127.5 million in grants for causes including nutrition and obesity research, anti-poverty research and public charter schools.

Amount donated in 2013: US$250 million Beneficiary: Yale University The former head of Franklin Resources pledged US$250 million to his alma mater to build two new residential colleges. He also holds a majority share of the San Francisco Giants baseball franchise.

Amount donated in 2013: US$225 million Beneficiaries: HopeLab, Humanity United, Omidyar Network, and the Ulupono Initiative Pierre Omidyar is the founder of eBay, while his wife, Pam, is the chairwoman of HopeLab, a nonprofit that develops technology to help critically ill children.

Amount donated in 2013: US$221.1 million Top beneficiary: The Jacobs Technion-Cornell Innovation Institute at Cornell NYC Tech Other notable gifts: Joan and Irwin Jacobs Fund at the Jewish Community Foundation of San Diego, Dunaway Foundation, San Diego Public Library Foundation Qualcomm co-founder Irwin Jacobs and his wife, Joan, made their largest pledge of about US$133 million to establish the Jacobs Institute, which will offer master's degrees in connective media, healthy living or the built environment.

Amount donated in 2013: US$219 million Top beneficiary: Brin Wojcicki Foundation Other notable gift: Michael J. Fox Foundation for Parkinson's Research Google co-founder Sergey Brin and 23andME founder Anne Wojcicki's foundation supports several causes, including human rights, the environment, women's issues and education. The couple split last year after six years of marriage.

Amount donated in 2013: Approximately US$212 million Beneficiary: Jeffrey Carlton Charitable Foundation Jeffrey Carlton, who died in 2012 at age 61, was the founder of metal processing company Press Forge. The foundation will provide support solely to four organisations: American Lebanese Syrian Associated Charities (the fundraising arm of St. Jude Children's Research Hospital), Hoag Hospital Foundation, Paralysed Veterans of America, and Principles (the nonprofit side of Impact Drug and Alcohol Treatment Centre).