S&P SmallCap 600 in Focus: PVA BLG

The index--which tracks stocks with a market capitalization between $300 million and $2 billion--gained 0.19 points to 393.37.

Small-cap companies make up about 3 percent of the total U.S. securities market, but are often cited as good investments due to their low valuations and potential to grow into big-cap stocks.

Year to date, the S&P SmallCap 600 is down 0.5 percent. It has outperformed the S&P 500, which has lost 4.7 percent.

Penn Virginia Corp. made the biggest gains on the index, surging $7.77, or 14.7 percent, to $60.77 after hitting a fresh all-time high of $62.92 earlier in the session.

Early Friday, the independent gas and oil company said it successfully drilled a natural gas test well in Texas with an initial production rate of 8 million cubic feet of natural gas per day. An RBC Capital Markets analyst said the production rate was double his estimates.

Power control systems maker Magnetek Inc. advanced 33 cents, or 9 percent, to $4.01.

Regional bank Guaranty Financial Group Inc. gained 37 cents, or 6.1 percent, to $6.45. On Thursday, shares lost 4.6 percent.

Among the decliners, Building Materials Holding Corp. plunged 43 cents, or 14.4 percent, to $2.56, and earlier hit a new low of $2.50.

All-terrain vehicle maker Arctic Cat Inc. tumbled 85 cents, or 10.1 percent, to $7.56.