SAN FRANCISCO (KRON) – On today’s edition of Rob Black’s Winners and Losers, our financial expert Rob Black and KRON 4’s Mark Danon talk about online shopping, mortages, and Michael Phelps.

Online stores such as Amazon have fundamentally reshaped the retail industry and how many workers are required. Internet sellers such as Amazon, eBay and Newegg are so good at what they do that there are 1.2 million fewer people working in the retail industry now than would be the case if online stores didn’t exist.

Five years after the housing recovery began, 5.9 million borrowers still owe more on their mortgages than their homes are worth. The so-called negative equity rate in the U.S. is falling, now at 12 percent of all mortgaged homeowners, down from more than 14 percent a year ago and more than 30 percent at the worst of the crisis.

Star Under Armour athlete Michael Phelps isn’t wearing Under Armour on the cover of Sports Illustrated. He’s wearing Nike. In 2012, the US Olympic Committee cemented a partnership with Nike that would last through 2020.

Rob Black answers Karen’s question: Can I use my 401k to pay for my medical bills?