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

Despite what would look like decent economic news on the surface, the broad-based S&P 500 (SNPINDEX:^GSPC) took to the red following a day of weak late-season earnings reports, and the prospect that the Federal Reserve will soon begin its monetary stimulus tapering.

Perhaps the biggest headline is the handshake agreement between Democrats and Republicans on a budget deal that will avert the possibility of another government shutdown early next year. The government shutdown in October proved to be less damaging than originally suspected to the U.S. economy, but clearly, no one wants to see another round of furloughs.

In the plus column, both the Mortgage Brokers Association weekly mortgage index, which showed a gain of 1% over the prior week, and a lower-than-expected federal budget deficit of $135.2 billion for November, helped in some small way buoy the S&P 500 from steeper losses.

By day's end, the S&P 500 ended decisively lower by 20.40 points (-1.13%), to finish at 1,782.22, its second straight down day, and its worst one-day performance in five weeks.

Bucking the trend, and leading all stocks to the upside today was commercial real estate investment firm NorthStar Realty Finance (NYSE:NRF), which surged 20.2% after announcing that its board had unanimously voted to spin off its asset management business into a separately traded public company by the second quarter of next year. The spin-off will be considered a tax-free distribution.

NorthStar Asset Management will enter into a 20-year agreement with NorthStar Realty Finance that will include the management of NorthStar Realty, a $90 million annual base management fee, and an additional annual base management fee of 1.5% of the cumulative equity raised in NorthStar Realty Finance after Dec. 10, 2013 paid to NRF, as well as additional incentives. Spin-offs are smart ways to unlock shareholder value in slow-growing commercial-REITs, and shareholders are clearly thrilled with today's news.

Hospital and outpatient rehabilitation operator Select Medical (NYSE:SEM) also rocketed to the upside by 18.1% for the day, despite the fact that there was no company-specific news. One macroeconomic factor that could have pushed Select Medical higher was today's release of the latest Obamacare sign-up figures. Although the 364,682 full enrollees are well-below the 7 million targeted by the government, simply seeing that enrollments more than doubled from last month bodes well for hospitals, which are looking to reduce their liability to uninsured and underinsured individuals. I've personally singled out Select Medical as one of the more attractive health-care value stocks out there, and feel that today's move could be sustainable with improving earnings data.

Finally, containership operator Global Ship Lease (NYSE:GSL) advanced 12.1% after announcing plans to issue $400 million in first priority secured notes due in 2021. Under normal circumstances, issuing debt isn't revered by investors; but as a shipping company, the need for excess liquidity is often paramount. In addition, credit ratings agency Moody's rated the company's offering as B3, with a stable outlook. Despite the obvious excitement of investors, I'm still left scratching my head, especially with daily charter rates still very weak. With the company soon to be boasting more than $800 million in net debt (with the assumption of the full $400 million secured note offering), I'd rather stick to the sidelines.