In trading on Tuesday, shares of the First Trust Brazil AlphaDEX Fund ETF ( FBZ) entered into oversold territory, changing hands as low as $18.59 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 Brazil AlphaDEX Fund, the RSI reading has hit 27.4 — by comparison, the RSI reading for the S&P 500 is currently 46.9. A bullish investor could look at FBZ's 27.4 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), FBZ's low point in its 52 week range is $17.88 per share, with $24.96 as the 52 week high point — that compares with a last trade of $18.59. First Trust Brazil AlphaDEX Fund shares are currently trading off about 3.8% on the day.