Ticker: BBG Short interest: 28% YTD return: 62% Sector: Oil and gas Comment: Bill Barrett has been able to increase the share of oil in its production stream to 25% from only 2% in 2008 to overcome low natural gas prices, but investors still seem unconvinced. Data from BloombergTicker: IMAX Short interest: 28% YTD return: 29% Sector: Entertainment Comment: IMAX shares could suffer if the New York Times' August report on waning interest in 3-D films holds. Data from BloombergTicker: ARO Short interest: 29% YTD return: -27% Sector: Retail Comment: Aeropostale is the worst-performing teen-clothing stock of the last three years, and is now considered a buyout target after a series of what Bloomberg's Tara LaChapelle describes as fashion misfires. Data from BloombergTicker: IOC Short interest: 29% YTD return: 18% Sector: Oil and gas Comment: InterOil's talks with Exxon over a natural gas facility recently faltered. Data from BloombergTicker: DDD Short interest: 29% YTD return: 69% Sector: 3-D manufacturing and printing Comment: 3D systems and other companies in the 3-D space continue to face investors who doubt the future of their technology. Data from BloombergTicker: FSL Short interest: 30% YTD return: 36% Sector: Semiconductors Comment: Freescale saw sales in two important divisions stagnate in its most recent fiscal quarter. Data from BloombergTicker: MILL Short interest: 31% YTD return: 61% Sector: Oil and natural gas exploration Comment: Miller's last two fiscal Q1s have seen operating losses. Data from BloombergTicker: X Short interest: 31% YTD return: 0% Sector: Steel Comment: US Steel was just downgraded to hold from buy by Deutsche Bank, which said its competitors offer better risk-reward plays. Data from BloombergTicker: PHH Short interest: 31% YTD return: 4% Sector: Business services Comment: PHH was just downgraded to neutral from buy by Sterne Agee, which said it is overvalued. Data from BloombergTicker: PPO Short interest: 31% YTD return: -8% Sector: Battery technology Comment: Polypore at one point lost as much as 10% in September after William Blair expressed concern about the pace of consumer demand in electric vehicles. Data from BloombergTicker: CLF Short interest: 31% YTD return: -30% Sector: Mining Comment: Cliffs missed earnings expectations and sales barely budged in its most recent fiscal quarter. Data from BloombergTicker: LF Short interest: 32% YTD return: -1% Sector: Children's education Comment: LeapFrog shares have lost -27% since the beginning of August. The company was downgraded in September by BMO Capital Markets to market perform from outperform on lack of confidence in the company's newest product line. Data from BloombergTicker: CHE Short interest: 32% YTD return: -3% Sector: Diversified Comment: Chemed shares lost -4% in the 24 hours after it reported net income and revenues had both declined YOY in its most recent fiscal quarter, and at $69 remain below their 12-month of $82 Data from BloombergTicker: ALJ Short interest: 32% YTD return: -34% Sector: Refining Comment: Alon told investors in its most recent fiscal quarter that the company had seen sharp cost increases from rising renewable fuel mandate prices. Data from BloombergTicker: RGR Short interest: 33% YTD return: 49% Sector: Guns Comment: Sturm, Ruger stock took a hit last week after retailer Cabela's said gun sales had fallen, though the shares have since rallied. Data from BloombergTicker: ESI Short interest: 33% YTD return: 66% Sector: Education Comment: ITT shares were recently confirmed as neutral by Merrill Lynch. The for-profit sector faces risks including fiscal uncertainty and competition from online courses. Data from BloombergTicker: WLT Short interest: 34% YTD return: -54% Sector: Coal Comment: Walter's earnings missed expectations on falling coal prices in its most recent fiscal quarter. Data from BloombergTicker: BZH Short interest: 34% YTD return: 0% Sector: Homebuilder Comment: Beazer shares have failed to recover to $20 after spiking to nearly $23 this summer, as housing market gains continue to slow. Data from BloombergTicker: USU Short interest: 35% YTD return: -46% Sector: Uranium Comment: USEC shares have fallen more than 80% to below $10 in the past two years as the nuclear industry confronts competition from cheap natural gas. Data from BloombergTicker: RSH Short interest: 36% YTD return: 29% Sector: Retail Comment: RadioShack's CEO recently warned that investors should expect an uneven performance over the next few quarters as the company implemented overhauling its stores, The Motley Fool reported. Data from BloombergTicker: NSM Short interest: 36% YTD return: 54% Sector: Housing Comment: Nationstar shares fell more than 7% last week as some economists interpreted the Fed's latest statement as indicating a tapering announcement could come as soon as January. Data from BloombergTicker: WNR Short interest: 37% YTD return: 12% Sector: Refining Comment: Western's net income fell sharply on weaker margins in its most recent fiscal quarter. Data from BloombergTicker: SLCA Short interest: 37% YTD return: 98% Sector: Refining Comment: U.S. Silica shares are subject to strong short interest because of the belief PE firm Golden Gate Capital will begin selling down its large position, Wells Fargo said in a recent note. The bank also downgraded the shares to market perform from outperform. Data from BloombergTicker: INVN Short interest: 39% YTD return: 40% Sector: Mobile Comment: InvenSense shares have fallen more than -10% in the last 30 days. The stock was dowgraded Oct. 30 by Roth Capital Partners on the company's weak guidance and a slowdown in high-end smartphone demand. Data from BloombergTicker: GY Short interest: 39% YTD return: 77% Sector: Aerospace and defense Comment: GenCorp's Aerojet unit saw a 14.5% decline in non-GAAP profits in the most recent fiscal quarter. Data from BloombergTicker: GY Short interest: 39% YTD return: -52% Sector: Rare earths and metals Comment: Molycorp has been hit hard by falling commodity prices. Data from BloombergTicker: HGG Short interest: 40% YTD return: 120% Sector: Retail Comment: hhgregg missed on earnings and revenues in its most recent fiscal quarter on flagging consumer confidence. Data from BloombergTicker: XON Short interest: 41% YTD return: -16% Sector: Biotech Comment: Intrexon IPO'd just this August, and shares have already lost about -16% of their value. Data from BloombergTicker: BTH Short interest: 83% YTD return: -18% Sector: Direct-to-consumer marketing Comment: Blyth sales fell 33% in its most recent fiscal quarter on poor performance by one of its marketing subsidiaries. Data from BloombergCheck out Credit Suisse's four events that would trigger a market correction »