In trading on Monday, shares of the PowerShares DB US Dollar Index Bearish Fund ETF ( UDN) entered into oversold territory, changing hands as low as $24.65 per share. We define oversold territory using the Relative Strength Index, or RSI, which is a technical analysis indicator used to measure momentum on a scale of zero to 100. A stock is considered to be oversold if the RSI reading falls below 30.In the case of PowerShares DB US Dollar Index Bearish Fund, the RSI reading has hit 29.8 — by comparison, the RSI reading for the S&P 500 is currently 62.2. A bullish investor could look at UDN's 29.8 reading as a sign that the recent heavy selling is in the process of exhausting itself, and begin to look for entry point opportunities on the buy side. Looking at a chart of one year performance (below), UDN's low point in its 52 week range is $24.65 per share, with $27.44 as the 52 week high point — that compares with a last trade of $24.68. PowerShares DB US Dollar Index Bearish Fund shares are currently trading down about 0.5% on the day.