In trading on Monday, shares of the Daily 20+ Year Treasury Bull 3x Shares ETF (TMF) entered into oversold territory, changing hands as low as $79.10 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 Daily 20+ Year Treasury Bull 3x Shares, the RSI reading has hit 28.3 — by comparison, the RSI reading for the S&P 500 is currently 55.2. A bullish investor could look at TMF's 28.3 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), TMF's low point in its 52 week range is $56.62 per share, with $113.35 as the 52 week high point — that compares with a last trade of $79.46. Daily 20+ Year Treasury Bull 3x Shares shares are currently trading down about 3.2% on the day.