WOW!

NEW YORK (Reuters) - Billionaire investor Warren Buffett is donating a total of $37 billion -- most of his personal fortune -- to a foundation started by Microsoft Chairman Bill Gates and to several family foundations, making it the largest-ever individual charitable gift in the United States.

Buffett, 75, is the chief executive of investment firm Berkshire Hathaway. He is worth an estimated $44 billion, according to Forbes magazine, making him the second-richest man behind Gates, who is worth about $50 billion.

The $37 billion comprises about 85 percent of Buffett's fortune.

In a letter to the Bill and Melinda Gates Foundation, Buffett, 75, said he will set aside 10 million shares of Berkshire class B common stock for the foundation.

Based on the stock's per-share price of $3071.01 as of Friday, the total amount for the Gates foundation comes to about $30 billion.

The amount is the largest commitment to a philanthropic cause ever made by one person in the United States, said Stacy Palmer, editor of the Chronicle of Philanthropy.

"Even if you look at what (John D.) Rockefeller and (Andrew) Carnegie gave historically -- even if you do it in today's numbers, it doesn't come close to that," she said.