In trading on Thursday, shares of the Proshares Ultra Utilities ETF ( UPW) entered into oversold territory, changing hands as low as $64.685 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 Proshares Ultra Utilities, the RSI reading has hit 27.3 — by comparison, the RSI reading for the S&P 500 is currently 46.3. A bullish investor could look at UPW's 27.3 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), UPW's low point in its 52 week range is $52.52 per share, with $77.90 as the 52 week high point — that compares with a last trade of $64.69. Proshares Ultra Utilities shares are currently trading down about 1.5% on the day.