Imagine losing a billion dollars in one week and not even flinching. If you're Warren Buffett, the chairman and chief executive officer of Berkshire Hathaway (BRK.A 0.64%), you won't need much of an imagination.

Thanks largely to the post-earnings plummet of IBM (IBM -0.89%) -- which was the fourth worst performing component on the S&P 500 (^GSPC -0.22%) last week, down by more than 10% -- Buffett did just that. According to data supplied by Standard & Poor's Capital IQ, his company's top five equity holdings lost a total of $934 million from when the market opened on Monday until it closed for the weekend on Friday. That equates to a loss of $9.3 million an hour, $155,657 a minute, and $2,594 a second.

Stock

Monday Open

Friday Close

Shares

Gain/(Loss)

Wells Fargo

$37.02

$36.69

466,410,061

($153,915,320)

Coca-Cola

$40.85

$42.66

400,000,000

$724,000,000

IBM

$210.44

$190.00

68,115,484

($1,392,280,493)

American Express

$65.53

$67.24

151,610,700

$259,254,297

Bank of America

$12.19

$11.66

700,000,000*

($371,000,000)

Source: Standard & Poor's Capital IQ.
*Relates to purchase warrants obtained in 2011.

IBM wasn't the only culprit. Following Bank of America's (BAC 1.53%) earnings release on Wednesday, the nation's second largest bank by assets fell precipitously, taking shares of Wells Fargo, the nation's fourth largest bank by assets, down with it.

Yet, all was not lost. Shares of Coca-Cola (KO 0.68%), Buffett's longtime favorite, rallied after the soft-drink maker impressed analysts and traders with the quality of its first-quarter results. And American Express similarly shot up following its own earnings announcement in the middle of the week.

It's worth nothing, moreover, that while these are Berkshire's largest public equity holdings, there are plenty others -- 44 others to be precise, according to Capital IQ. In addition, Berkshire's stock portfolio is only one component, and a small one at that, of its larger operational superstructure, which includes full ownership stakes in the likes of GEICO Auto Insurance, See's Candy, and Burlington Northern Santa Fe, to name only a few. It's for this reason, in turn, that Buffett probably didn't even bat an eye last week.