Individual stocks can surge 10%, 25%, or even higher in a short period of time. And they can fall just as far, just as quickly. For example, shares in DryShips have fallen nearly 35% since May 7, in part because the company sent another shot across the bow of the shipping sector when it announced its third equity offering to help deal with debt.

Big drops in share price can sometimes signal material defects or new risks. But at other times, they're simply pullbacks that come along with the larger pessimism facing the market today. Fortunately, we have Motley Fool CAPS, a great resource to help us understand the larger picture behind big price drops.

Is the sky falling?
CAPS contains more than just the crowd's opinions. Its best-performing members' votes count more in shaping each company's rating than do the picks of their poorer-performing peers. That way, investors can intelligently use the collective wisdom of more than 130,000 CAPS members to make better decisions.

We'll use CAPS' handy stock screening tool to quickly zero in on companies that have been slashed by at least 20% in the past four weeks and have a market cap greater than $100 million and a beta of less than 3. If you want to run this screen for yourself, please do -- just keep in mind that the results will update with the market.

Company

CAPS Rating
(Out of 5)

4-Week
Price Change

US Airways (NYSE:LCC)

*

(20.4%)

YRC Worldwide (NASDAQ:YRCW)

**

(20.6%)

NVIDIA (NASDAQ:NVDA)

****

(27.6%)

Source: Motley Fool CAPS. Price return April 17 through May 14.

US Airways
US Airways traffic fell year over year in March and April, and the number of people flying on U.S. airlines overall in February had its largest single-month decline in seven years. Flu fears have prompted several airlines -- including US Airways, Continental (NYSE:CAL), and United Airlines parent UAL (NASDAQ:UAUA) -- to curtail flights to Mexico, which an increasing number of fliers are avoiding.

The recent rise in oil costs has begun to place more pressure on shares of airline companies across the board. US Airways raised more than $200 million of additional capital recently to help it navigate the rough economy, but many CAPS members have a host of reasons for staying away from airlines right now. In CAPS, only 53% of the 655 members rating US Airways expect it to outperform the market.

YRC Worldwide
Air transportation is really hurting, but things aren't looking much better in land-based transport, either. Major trucking company YRC Worldwide has been in survival mode lately, and some investors fear that the company won't be able to cut enough costs to meet its credit requirements and would then need to work out an agreement with creditors. YRC faces an estimated $2 billion in pension obligations over the next four years with monthly obligations toward a troubled multi-employer pension fund that UPS (NYSE:UPS) paid to withdraw from several years ago. The company is looking to the government for help with plans to ask for $1 billion in TARP money, but some investors think the chances of a trucking bailout are slim. At this point, a rather soft 77% of the 319 CAPS members rating YRC Worldwide expect it to beat the market.

NVIDIA
NVIDIA posted a quarterly loss that was better than what the average Wall Street analyst was looking for recently. It even brought in positive free cash flow of $121.4 million. But investors beat shares down after the results, unhappy with lower gross margins compared with last quarter. The graphics-processor company posted better-than-expected sales, which increased sequentially. It also got rid of some inventory and picked up market share in stand-alone GPUs, which compete with AMD (NYSE:AMD), for the second straight quarter. Despite the poor showing, many CAPS members remain bullish, with nearly 96% of the 4,479 members rating NVIDIA believing that the company will outperform the broader market.

Ultimately, whether or not you believe a fall in any stock is warranted, your own research is more important than collective opinions. CAPS can help you quickly focus your due diligence and even point out potential pitfalls you may not have seen.

Add your take on these or any of the more than 5,300 stocks that 130,000-plus members have covered in Motley Fool CAPS. It's totally free to be a part of the community, and the payback is more than worth it.