Each business day, TheStreet.com Ratings TheStreet.com Ratings compiles a list of the top five stocks in one of five categories -- fast-growth, all-around value, large-cap, mid-cap and small-cap -- based on data from the close of the previous trading session. Today we focus on mid-caps.

These are stocks of companies that have market capitalizations of between $500 million and $10 billion that rank near the top of all stocks rated by our proprietary quantitative model, which looks at more than 60 factors.

The stocks must also be followed by at least one financial analyst who posts estimates on the Institutional Brokers' Estimate System. They are ordered by their potential to appreciate.

Note that no provision is made for off-balance-sheet assets such as unrealized appreciation/depreciation of investments, market value of real estate or contingent liabilities that might affect book value. This could be material for some companies with large underfunded pension plans.

DeVry ( DV) is an international higher education company that operates DeVry University, Ross University, Chamberlin College of Nursing, and Becker Professional Review. The company has been rated a buy since January 2007. DeVry's strengths can be seen in a variety of areas, such as its impressive record of earnings-per-share growth, robust revenue growth, return on equity and largely solid financial position. Solid stock price performance also contributes to the buy rating.

The company announced on Jan. 27 that its revenues rose 35% year over year in the second quarter of fiscal 2009, helped by increased revenue across segments and the acquisition of U.S. Education, which is the parent company of Apollo College and Western Career College. Revenue growth appears to have trickled down to the bottom line, as DeVry reported EPS improvement of 20.4%. Higher enrollment numbers also helped boost earnings. Net income also increased, rising to $42.9 million from $35.8 million in the second quarter of fiscal 2008. Return on equity, which improved slightly when compared to the same quarter a year ago, can be seen as a modest strength for the organization. In addition, a debt-to-equity ratio of 0.2 indicates that DeVry has successfully managed its debt levels.

Management was pleased not only with DeVry's financial results in the second quarter, but also with the employment rate of its graduates. Management stated that it was remarkable in the current job market to see 92% of recent graduates employed within six months of graduation. The company continues with a conservative capital structure that it feels is appropriate to the current economic climate, although it does continue to invest in growth opportunities. Looking ahead, DeVry expects its full year 2009 capital expenditure to be in the range of $65.00 million to $70 million. Although the company shows low profit margins, we feel that the strengths detailed above outweigh any weaknesses at this time.

Shenandoah Telecommunications ( SHEN - Get Report) provides regulated and unregulated telecommunications services, including local exchange telephone services, wireless personal communications services, cable television, video, and Internet and data services, long distance, and other services through its wholly owned subsidiaries. The company has been rated a buy since April 2008 on the basis of its revenue growth, largely solid financial position, expanding profit margins and other strengths.

For the third quarter of fiscal 2008, Shenandoah Telecommunications reported revenue growth of 14.6% year over year, which was higher than the industry average of 4%. This growth appears to have trickled down to the company's bottom line, as earnings per share rose 23.1% when compared to the same quarter last year. Net income also increased, rising 33.3% from $5.1 million to $6.8 million. The company has a very low debt-to-equity ratio of 0.1, indicating that debt levels have been successfully managed, along with a quick ratio of 1, which illustrates Shenandoah Telecommunications' ability to avoid short-term cash problem.

Management stated that the company made solid performance improvements in the third quarter, along with progress in expanding its PCS network and offering further data and push-to-talk services. Although we consider the company's stock to be trading at a premium valuation based on our review of its current price compared to factors like earnings and book value, we feel that the strengths detailed above outweigh any weaknesses and justify the high price level at this time.

ManTech International ( MANT - Get Report) provides technologies and solutions for mission-critical national security programs for the intelligence community, the space community, and various departments and agencies of the U.S. federal government. ManTech has been rated a buy since March 2005. Our rating is based on strengths such as the company's robust revenue growth, largely solid financial position, and record of EPS growth.

For the third quarter of fiscal 2008, revenue rose by 26.8% year over year. This increase was primarily the result of a business strategy focused on high-end defense and intelligence markets supporting U.S. national security. Revenue growth appears to have helped boost earnings per share, which improved 31.4% when compared to the same quarter a year ago. The EPS increase from 51 cents to 67 cents represents the continuation of a pattern of positive EPS growth demonstrated by ManTech over the past two years, a trend which we feel should continue. Net income also increased in the third quarter, rising from $17.5 million in the third quarter of fiscal 2007 to $23.9 million in the most recent quarter. ManTech's very low debt-to-equity ratio of 0.007 and quick ratio of 1.4 illustrate the company's successful management of debt levels and ability to avoid short-term cash problems.

Management announced it was pleased with the third quarter results, as strong performance and excellent cash flow helped provide necessary flexibility in a challenging economic environment. Based on strong business momentum in its national security and defense business, the company set EPS guidance at 67 cents to 70 cents for the fourth quarter and $2.53 to $2.56 for full-year fiscal 2008. These ranges represent 10% to 15% growth over the fourth quarter of fiscal 2007 and 30% to 31% growth over full-year fiscal 2007. The company currently shows low profit margins, but we feel that the strengths detailed above outweigh any potential weakness.

Haemonetics ( HAE - Get Report) is a global leader in blood processing technology, designing, manufacturing, and marketing automated blood processing systems and single use consumables for blood donors and surgical patients. Our buy rating for Haemonetics has been in place since February 2004, based on such strengths as the company's robust revenue growth, largely solid financial position, improvement in net income and EPS, and solid stock price performance.

For the third quarter of fiscal 2009, the company reported on Feb. 2 that its revenue rose 15.5% year over year, with double-digit growth recorded across all geographies. This improvement slightly outpaced the industry average of 13.6%. It also appears to have trickled down to the company's bottom line, as EPS increased 14.8% when compared to the same quarter a year ago. Net income grew 13.1%, rising from $14.3 million to $16.2 million. Haemonetics has a very low debt-to-equity ratio of 0.02, implying that it has successfully managed its debt levels. In addition, a quick ratio of 2.9 indicates that the company has the ability to cover its short-term cash needs.

Due to stronger-than-planned sales of plasma disposables, blood bank disposables, and equipment and the strong third quarter revenue results from all geographies, Haemonetics raised its full year revenue guidance. The company now anticipates revenue growth of 15% to 16%, up from previously announced expectations for 12% to 14% full year revenue growth. The company shows somewhat disappointing return on equity, but we feel that the strengths detailed above outweigh any potential weakness at this time.

California Water Service Group ( CWT - Get Report) is a holding company that provides water utility and other related services in California, Washington, New Mexico, and Hawaii through its subsidiaries. It produces, purchases, stores, treats, tests, distributes, and sells water for domestic, industrial, public, and irrigation uses, as well as for fire protection. We upgraded California Water Service Group to a buy in August 2008. Our rating is based on a number of company strengths, including its revenue and net income growth, impressive record of EPS growth, expanding profit margins, and good cash flow from operations.

For the third quarter of fiscal 2008, the company's revenue rose 15.7% year over year. Revenue growth appears to have helped boost EPS, which improved over the past year from 67 cents to $1.06. Net income also increased when compared to the same quarter a year ago, climbing 60.6% from $13.8 million to $22.2 million. We consider the company's gross profit margin of 37.6% to be strong. It has increased from the same quarter of fiscal 2007. In addition, the net profit margin of 16.80% is above that of the industry average. Furthermore, net operating cash flow has increased significantly, rising 86.6% to $48.3 million.

Looking forward, California Water Service Group expects to be able to pursue water efficiency programs in order to benefit ratepayers and reduce overall water demand. Although the company may harbor some minor weaknesses, we fell they are unlikely to have a significant impact on results.

Our quantitative rating, which can be viewed for any stock through our stock screener stock rating screener, is based on a variety of historical fundamental and pricing data and represents our opinion of a stock's risk-adjusted performance relative to other stocks.

However, the rating does not incorporate all of the factors that can alter a stock's performance. For example, it doesn't always factor in recent corporate or industry events that could affect the stock price, nor does it include recent technology developments and competitive dynamics that may affect the company.

For those reasons, we believe a rating alone cannot tell the whole story and should be part of an investor's overall research.