Converted to today's dollars, during his lifetime the industrialist Andrew Carnegie gave away $8 billion of his $10.3 billion net worth, or 78 percent, according to Carnegie Corp. figures.
Microsoft mogul Paul Allen, net worth $16 billion, gave away one-third of 1 percent of his fortune.
Oracle magnate Larry Ellison, net worth $20 billion, half of 1 percent.
Pierre Omidyar, founder of eBay, net worth $7.7 billion, less than 1 percent.
Nike tycoon Philip Knight, net worth $7.9 billion, slightly more than 1 percent.
For the average person to keep much more than he or she gives is understandable; for the super-rich, it's a different matter.
[Excerpt of an article by Gregg Easterbrook, The San Jose Mercury News]