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.

In just a few days, the question of whether our federal government will shut down has morphed into a question about what will happen once it does. While many worry that the shutdown will slow an already-fragile economic recovery, the debt ceiling debate remains the larger issue for Congress to solve this week. If the U.S. defaults on its debt, the effects could be disastrous, driving up borrowing costs for the world's biggest economy.

Needless to say, the massive issues facing Congress right now struck fear into Wall Street, as some Washington approval ratings fell to all-time lows. The S&P 500 Index (SNPINDEX:^GSPC) dropped 10 points, or 0.6%, to end at 1,681. 

The worst performer in the benchmark index on Monday was J.C. Penney (NYSE:JCP), which lost 2.7% today. A range of nightmares -- from the company's decision to abolish sales promotions last year to its recent desperate fundraising attempt via the issuance of 84 million additional shares -- has made J.C. Penney a familiar name on this list. But Monday brought a whole new level of psychological terror for shareholders: The stock reached its lowest level since 1982, Reagan's first term. 

The second-biggest loser, next to J.C. Penney, was telecom services provider Frontier Communications (NASDAQ:FTR), which shed 2.6%. Perhaps at first glance you'd think Frontier's 9.3% dividend screams buy, but all that glitters is not gold. It pays out in dividends four times what it earns each year, a trend that must end to be sustainable. 

Business information services company Iron Mountain (NYSE:IRM) rounds out today's list, falling 2.5%. While there was no clear catalyst behind the move, Iron Mountain's current valuation doesn't lend itself well to appreciation: The company trades at 40 times trailing earnings. Did I mention its earnings have also been wildly erratic over the last five years? You can pardon a risk-averse Wall Street on Monday for passing on this stock. 


Fool contributor John Divine has no position in any stocks mentioned. You can follow him on Twitter @divinebizkid and on Motley Fool CAPS @TMFDivine.

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