Jeff Bezos and Elon Musk are among the 156 billionaires on the Forbes 400 who have given less than 1% of their wealth to charity

• Billionaires including Jeff Bezos and Elon Musk reached new record levels of wealth last year.
• Billionaires are also less generous than ever in terms of share of wealth they've given away.
• Of the Forbes 400, a record 156 - including Bezos and Musk - have given less than 1%.

While Jeff Bezos and Elon Musk feud over who is wealthier and who is more litigious, the business titans are among a group of billionaires in the running for an even less desirable title: World's Stingiest Billionaire.

Although the pandemic era's surging stock market has ballooned the fortunes of billionaires to new heights, the wealthiest people in the world have chosen not to keep pace with their charitable giving, according to the Forbes Philanthropy Score.

The team at Forbes adds up all of the lifetime "out-the-door" giving a person has made, and divides that number by the sum of their total current wealth and the total giving amount. The results are categorized into five tiers: less than 1%; between 1% and 5%; between 5% and 10%; between 10% and 20%; and 20% or more.

Private foundations and donor-advised funds don't count for the Forbes measure, since those "donations" effectively remain under the control of the donor, and also come with generous benefits that enable wealthy people to avoid paying taxes.

If the median American household gave $1,200 to charity across their entire lives based on a present net worth of about $120,000, Forbes would consider that more generous than Bezos and Musk based on this metric.

Of the 400 billionaires on this year's list, just 19 have given away 10% or more of their wealth, while a record high 156 have given less than 1%. While Bezos and Musk have yet to crack out of the 1%, MacKenzie Scott has left them in the dust by giving away 13% of her fortune. Even with her pace of giving, Scott is wealthier now than she was last year.

Bezos did make headlines this summer with $400 million gifts to the Smithsonian, Van Jones, and Jose Andres, and has given $865 million from his pledge to fight climate change. But his actual gifts are a tiny fraction of the $22 billion gain he made this year alone, to bring his total net worth to $201 billion.

Warren Buffet continued as the list's most generous giver, having parted with $4.1 billion of Berkshire Hathaway stock in June to bring his lifetime total to $44 billion. He's now halfway through his pledge to give away all his Berkshire shares.

The most prolific giver in the Forbes ranking was George Soros, whose $16.8 billion of giving has outsized his $8.6 billion net worth. Former president Donald Trump was not ranked, since he fell $400 million shy of making the top 400 list.