In trading on Friday, shares of the First Trust CBOE S&P 500 VIX Tail Hedge Fund ETF ( VIXH) entered into oversold territory, changing hands as low as $20.81 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 First Trust CBOE S&P 500 VIX Tail Hedge Fund, the RSI reading has hit 29.2 — by comparison, the RSI reading for the S&P 500 is currently 54.1. A bullish investor could look at VIXH's 29.2 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), VIXH's low point in its 52 week range is $18.50 per share, with $22.25 as the 52 week high point — that compares with a last trade of $20.81. First Trust CBOE S&P 500 VIX Tail Hedge Fund shares are currently trading off about 3.1% on the day.