There were 1,173 million-dollar-plus charitable donations in 2013, down from 1,408 in 2012. But the 2013 gifts totalled $16.92 billion, up from $13.96 billion a year earlier according to the bank's Million Pound Donors Report.
Three large donors dominated the field, with the largest new gift coming from the Bill and Melinda Gates Foundation, which gave the World Health Organization some $1.8 billion last year.
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Warren Buffett gave $2 billion to the Bill and Melinda Gates Foundation, an annual contribution to the foundation as a result of a $30 billion pledge he made in 2006.
Mark Zuckerberg and his wife, Priscilla Chan, gave $1 billion to the Silicon Valley Community Foundation.
Of the $16.9 billion in gifts to charity last year, 21 percent of them were over $10 million – up from 17 percent the year before.
Donors on the west coast of the U.S. gave the largest proportion of the total value of gifts worth one million dollars or more, at 38 percent thanks to gifts from Zuckerberg and Chan and the Gates Foundation, which are both located in the region.
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Meanwhile in the U.K. 292 donations over £1 million ($1.6 million) were made last year, marking a 50 percent increase on the number of gifts made in 2012, but the total value of the amount donated grew less than 1 percent.
London kept its status as the centre of U.K. philanthropy, producing the vast majority of million pound donors, with 169 donations and 69 percent of the total.
"It is very encouraging to see such a large number of million pound donations. This finding marks a new stage in UK philanthropy, when 'giving a million' becomes the new normal for those that have the capacity to give at the highest leve,"l said Dr Beth Breeze from the Centre for Philanthropy at the University of Kent co-author of the U.K. report.
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"We have long known that social norms and social pressure are key to encouraging philanthropy: the heightened attention on major givers in the media, and the increasingly positive climate for philanthropy in the U.K., have combined to nudge people towards making more significant donations than they might otherwise have done," she said.
Higher education as a sector received more donations globally than any other sector – taking in 692 million-dollar-plus donations, amounting to around $9 billion.
Charitable foundations came in second place and were given almost $5 billion, followed by public and social benefits and healthcare.