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.

This morning the weekly jobless-claims report was published, and it fell to its lowest level since 2007. The Department of Labor said the seasonally adjusted 320,000 claims was the lowest it had been since October of 2007. Economists were expecting a reading of 335,000, which would certainly have been good, but not as strong as what we got. However, the better the economic data, the more fearful investors become that the days of cheap money will soon end when the Federal Reserve begins slowing its $85 billion-per-month bond-buying program. 

Almost immediately after the report was released, Treasury rates jumped. The yield on five-year notes rose from 1.47% to 1.54%, the 10-year jumped from 2.71% to 2.78%, and the 30-year climbed from 3.75% to 3.8%.

These bond yields and the fear that rates will continue to rise have caused the markets as a whole to tumble today. As of 12:55 p.m. EDT the Dow Jones Industrial Average (DJINDICES:^DJI) is down 186 points, or 1.21%, to 15,152. The S&P 500 and the Nasdaq are mixed have fallen 1.19% and 1.37%, respectively. All of the Dow's 30 components are in the red. Let's take a quick look at two of the worst performers of the day.

Shares of Cisco (NASDAQ:CSCO) have plunged 6.3% today after the company announced a 5% cut to its workforce and, more importantly, lowered its guidance for future quarters. This comes despite the fact that Cisco met Wall Street's expectations in yesterday's after-hours earnings report. 

Wal-Mart (NYSE:WMT) is also having a rough day after announcing its quarterly earnings and lowering future expectations: Shares are down 2.4%. The company cut its revenue-growth forecast in half for the remainder of the year, citing higher payroll taxes and gasoline prices as two reasons consumers aren't spending more.  

Yesterday I wrote about how investors need to focus on actual numbers, rather an analyst's expected quarterly results. Today both Wal-Mart and Cisco are trading lower not because of what they reported for the past quarter, but because of what management believes the company will report in the future. Even though management certainly knows more about the business than anyone else, investors need to stick to hard numbers when making a decision. As we have seen in the past, CEOs, CFOs, and board directors have as good of a track record predicting the future as analysts do: They are only right about 50% of the time.

If the management team had said that a major shift in the industry was causing sales to fall and would definitely reduce profit this year, that would be a different story. But a simple lowering of revenue guidance shouldn't be a reason for a long-term investors to run for the hills. If anything, this could be a nice buying opportunity today.