NEW YORK (TheStreet) -- Micro-cap stocks have taken investors on a rough ride. In 2008, the Morgan Stanley Capital International U.S. Micro Cap Index dropped 44%, lagging the S&P 500 Index by 6 percentage points. The index has recovered this year, rising 38% and outpacing the S&P 500 by more than 25 percentage points.
The recent performance highlighted the appeal of these stocks, the smallest of the market. Although they can be extremely volatile, micro caps have outperformed the S&P 500 over long periods. During the 35 years ending in June, micro caps returned 14% annually, while large stocks returned 9.6%, according to Merrill Lynch, a unit of Bank of America
Micro-cap stocks can help diversify portfolios because they don't always move in lockstep with the S&P 500. Adding a mutual fund that owns a mix of small and large stocks might help smooth out long-term results.
To appreciate the strengths and weaknesses of micro caps, consider the performance of the Wasatch Micro Cap Fund
During the downturn that began in 2000, the fund shined. At the time, investors were dumping large technology stocks and shifting to small value names. With money gushing into micro caps, Wasatch returned 50% in 2001, outdoing the S&P 500 by 61 percentage points, according to Morningstar
During the disastrous year of 2008, Wasatch lost 49%, trailing the S&P 500 by 12 points. For all the ups and downs, the fund boasts a strong long-term record, returning 12.0% annually during the past decade, outdoing the S&P 500 by 13 percentage points.
Definitions of micro caps vary. Some analysts limit the field to stocks with market capitalizations less than $500 million, while others consider the cut-off point to be $250 million. Perritt Capital Management includes the approximately 2,200 stocks that have capitalizations less than $450 million. The median capitalization of the group is $95 million.
By many measures the category is small, with a total market cap of around $300 billion, according to Perritt. In comparison, Exxon Mobil
The small size helps explain why micro caps can be so volatile. If just a bit of money leaves the group, the shares can plummet. That happened last year when panicked investors dumped shakier micro caps and took refuge in Treasuries.
To hold micro caps, consider relying on a well-diversified fund. A top choice is the Royce Micro-Cap Fund
Royce & Associates looks for stocks with sound balance sheets, making them more resilient in economic downturns. The portfolio includes beaten down stocks along with companies with rapidly growing earnings. Morningstar often classifies it as a "blend" fund because it holds growth and value shares.
A favorite holding is The Buckle
"This company has a solid balance sheet and a long track record for maintaining healthy returns on equity," says Royce portfolio manager Jennifer Taylor.
Another diversified fund is the Perritt Micro Cap Opportunities Fund
Portfolio manager Michael Corbett looks for companies that are improving their cash flow and profit margins, and cutting their debt. The fund holds some growth and value names. Most of the businesses focus on strong niches.
Corbett likes John B. Sanfilippo & Son
The Heartland Value Fund
The fund owns shares of Ensign Group
-- Reported by Stan Luxenberg in New York.
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