6. Anne Cox Chambers
Net Worth: $10.7 billion
Source of wealth: Cox Enterprises
Age: 92
Overall Rank: 32
At age 92, Chambers continues to sit on the board of privately held Cox Enterprises, which owns cable company Cox Communications, the Cox Media Group of newspapers, TV and radio stations, the Manheim automobile auction and AutoTrader.com. Her father, James M. Cox (d.1957), founded the company in 1898.