Top earners

Microsoft co-founder Bill Gates remains America’s richest man, taking the top spot on the list for the 20th straight year. Forbes estimates his net worth at $72 billion, up from $66 billion a year ago.

The rest of the top 10:

Warren Buffett of Berkshire Hathaway: $58.5 billion.

Larry Ellison of Oracle Corp.: $41 billion.

Charles Koch of Koch Industries: $36 billion

David Koch of Koch Industries: $36 billion.

Christy Walton and family, WalMart heirs: $35.4 billion.

Jim Walton, WalMart heir: $33.8 billion.

Alice Walton, WalMart heiress, $33.5 billion.

S. Robson Walton, WalMart heir, $33.3 billion.

Michael Bloomberg of Bloomberg LP: $31 billion.

Source: forbes.com/forbes400

Charleston resident, business leader and philanthropist Anita Zucker has climbed 20 spots on Forbes magazine’s annual ranking of the 400 wealthiest Americans.

She was the only South Carolinian on the updated list, which was released Monday.

The business publication estimated that Zucker’s wealth climbed $500 million, or 24 percent, from a year ago to $2.6 billion. That put her in the 209th spot for 2013.

Zucker is CEO and chairwoman of The InterTech Group Inc., a North Charleston-based global manufacturing conglomerate with interests in chemicals, specialty textiles, utilities, real estate and aerospace.

Locally, the privately held, family-run business owns the Carolina Stingrays hockey team, Carolina Ice Palace and a couple of Charleston restaurants.

Also, its TIGHITCO subsidiary this year completed the first phase of a North Charleston manufacturing plant that makes composite aircraft parts.

InterTech has annual sales of about $4 billion, according to Forbes.

Zucker, 62, is the widow of Jerry Zucker, who founded the company in 1982. He died in 2008 from a brain tumor. Their oldest son, Jonathan, is president of the company.

InterTech had nothing to add to the report, Robert Johnston, executive vice president, said in an email late Monday.

The 2013 edition of the Forbes 400 showed that life has been good for America’s super wealthy. While most of the top names and rankings didn’t change from a year ago, the majority of the elite club’s members saw their fortunes grow over the past year, helped by strong stock prices and the rebound in real estate values.

“Basically, the mega rich are mega richer,” said Kerry Dolan, a Forbes senior editor.

Dolan said the minimum net income for the Forbes 400 returned to a pre-financial crisis level of $1.3 billion, up from $1.1 billion in 2012, with 61 American billionaires not making the cut.

“In some ways, it’s harder to get on the list than it ever has been,” she said.

The Associated Press contributed to this report.