Although we don't believe in timing the market or panicking over daily movements, we do like to keep an eye on market changes -- just in case they're material to our investing thesis.

A second straight day of unabashed bullishness on Wall Street sent seven out of 10 stocks higher Friday. You'd think that a rally of this magnitude would be backed up by a firm deal on the debt ceiling or, perhaps, at the very least, an agreement to reopen the government. In reality, neither issue was resolved -- the two quibbling parties simply agreed to keep quibbling into the weekend. Whether it's a tribute to the political discord, or Wall Street's current mind-set, isn't entirely clear, but either way, the S&P 500 Index (^GSPC 0.31%) added 10 points, or 0.6%, to end at 1,703 on Friday. 

Despite the euphoric atmosphere, a number of S&P components ended steeply in the red. Chipmaker Micron Technology (MU 2.48%) stumbled 8.6% today, a day after the company reported fourth-quarter fiscal results. The fall is highly unusual in that it comes as a number of analysts boosted their price targets on the stock, and complimented Micron's quarter. The stock is certainly no stranger to volatility, which may be behind the sell-off today, as investors cash out on gains; the stock is up more than 160% this year. 

Newmont Mining (NEM 2.27%) finds itself among the day's worst performers again Friday, dipping 2.6% as the market reacted to yesterday's announcement that Newmont would be shipping out far less copper than expected this year. Adding to investors' frustration is the fact that gold prices are plummeting, putting further pressure on the miner's already diminished outlook. Gold fell 2.2% today, as fears continued to ease about the debt ceiling. 

Lastly, business services and storage company Iron Mountain (IRM -0.42%) lost 2.2% as several major developments gave shareholders pause. The company's current CFO, who's been in his current position since 2007, will be stepping down at the end of the month to pursue other opportunities, leaving an interim CFO in his place. Barclays also downgraded Iron Mountain as a result of the CFO departure today, seeing it as a sign that its attempt to be classified as a REIT for tax purposes will fail.