In trading on Tuesday, shares of the Guggenheim Canadian Energy Income ETF ( ENY) entered into oversold territory, changing hands as low as $15.1301 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 Guggenheim Canadian Energy Income, the RSI reading has hit 29.0 — by comparison, the RSI reading for the S&P 500 is currently 48.3. A bullish investor could look at ENY's 29.0 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), ENY's low point in its 52 week range is $13.75 per share, with $17.69 as the 52 week high point — that compares with a last trade of $15.21. Guggenheim Canadian Energy Income shares are currently trading off about 1.1% on the day.