In trading on Friday, shares of the BLDRS Developed Markets 100 ADR Index Fund ETF (ADRD) entered into oversold territory, changing hands as low as $20.191 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 BLDRS Developed Markets 100 ADR Index Fund, the RSI reading has hit 28.9 — by comparison, the RSI reading for the S&P 500 is currently 38.4. A bullish investor could look at ADRD's 28.9 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), ADRD's low point in its 52 week range is $17.69 per share, with $23.63 as the 52 week high point — that compares with a last trade of $21.21. BLDRS Developed Markets 100 ADR Index Fund shares are currently trading off about 1.8% on the day.