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.

If you've been following the markets, reading the news, watching TV, or speaking with other human beings, you're probably aware that there's a government shutdown going on and the U.S. is at risk of an unprecedented debt default. But you'd never know anything was amiss if you'd sat at your computer watching the S&P 500 Index (^GSPC 0.31%) tick this way and that, though you'd probably realize you needed to get out of the house. Despite the political impasse in Washington, the S&P 500 managed to tick a little higher, adding about 1 point, or 0.1%, to end at 1,656.

There were plenty of decliners in the S&P, of course, as there always are. Often the day's worst performers have a common theme: Maybe they belong to a certain sector that fared poorly, maybe they're reliant on high gold prices for growth. Who knows. But again and again, a theme arises. Yesterday's was so powerful it continued into today, bringing two repeat offenders to the day's list.

Netflix (NFLX -1.16%) is the first and most prominently declining repeat offender, shedding 4.6% on Wednesday on double its average volume. Yesterday's theme, which saw highly popular momentum stocks and stocks with hefty P/E ratios get hammered, continued to be the catalyst behind Netflix's fall from glory. Even though shares have cratered more than 10% in the last two days of trading, Netflix is still up more than 200% in 2013. 

Vertex Pharmaceuticals (VRTX -0.58%), the lone newbie on the list, dropped 2.9%, although it too has posted enormous gains this year. The biotech company, which develops treatments for a variety of serious diseases from hepatitis C to cystic fibrosis, is up 67% this year. It lost more than 4% yesterday, but with so many severe sell-offs on Wall Street on Tuesday, Vertex's mere 4% decline didn't even qualify.

Lastly, Alexion Pharmaceuticals (ALXN) rejoins the list, falling 2.8%. Alexion's stock, which trades at 60 times earnings, has had a rough go of it this week, falling nearly 10% in just three days. It doesn't take a mind reader to deduce the message Wall Street is sending this week: Now is not the time for growth stocks. Of course, from a long-term perspective, beaten-down growth stocks like the three on today's list may very well be fine additions to your portfolio. It would be wise to first determine whether you believe the government is dysfunctional to the point where it's willing to default on its own debt. Because if that's the case, you can stop bargain hunting right then and there. Far more alluring sales lie ahead.