The Dow Jones Industrial Average (^DJI 0.63%) continues to amaze. After going on a run of record-breaking days back in the spring, than tanking and losing nearly 5%, the market has once again reversed course and is back to its old ways of setting record highs on a consistent basis. On Monday and Thursday, the Dow set new all-time closing highs, while also setting a new all-time intraday high on Thursday. For the week, the blue-chip index closed higher by 79 points, or 0.51%, and now sits at 15,543. The S&P 500 had a slightly better week, gaining 0.7%, but the Nasdaq lost ground over the past five trading sessions, as it ended the week down 0.34%.

Before we hit the Dow losers, let's look at this week's best performing component. Bank of America (BAC 1.34%) increased by 7.03% for the week after the company released strong earnings and got an upgraded price target from UBS. Nearly all of the banks that have reported results up to this point have impressed investors, and Bank of America certainly fell into that category. UBS believes Bank of America can continue to improve earnings if it remains diligent on cost controls. That's a great sign that the company can continue showing strong profits despite whatever pace the economy recovers at.

The big losers
Shares of Microsoft (MSFT 1.51%) led all Dow losers this past week with an 11.97% drop, largely spurred by a poor earnings report. The company's release didn't paint a great picture of the Surface tablet, on which Microsoft took a $900 million charge-off. In addition, the company's most important product, Windows, showed weakness in Q2. That was perceived not just as a problem for Microsoft, but for the PC industry as a whole. 

And that's why Hewlett-Packard (HPQ 0.43%) came in as the third worst Dow component of the week, with shares down slightly more than 4%. As signs continue to point toward a weak PC industry, and with shares of Hewlett-Packard up more than 76% year to date, investors began selling off the once-dominant PC company. And although Meg Whitman is attempting to move the company away from relying on PC sales, HP still needs the industry to remain strong in the interim, and Microsoft's weakness in that area didn't give investors the confidence they were looking for.

Finally, American Express (AXP 2.26%) was the second worst Dow stock of the week, as shares declined 5.45% after not one, but two firms downgraded the company after it beat second-quarter earnings estimates and posted revenue more or less in line with expectations. Both downgrades came as a result of a possible European Commission ruling that would limit debit and credit card transaction fees to 0.2%. One analyst has estimated that such a restriction would cost American Express around $4.5 billion in fees.

The other Dow losers this week:

(For more information on why shares of the other losers fell lower this past week, click on the following links.)