In trading on Tuesday, shares of the SPDR Barclays Aggregate Bond ETF ( LAG) entered into oversold territory, changing hands as low as $57.09 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 SPDR Barclays Aggregate Bond, the RSI reading has hit 29.9 — by comparison, the RSI reading for the S&P 500 is currently 38.6. A bullish investor could look at LAG's 29.9 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), LAG's low point in its 52 week range is $56.68 per share, with $59.57 as the 52 week high point — that compares with a last trade of $57.16. SPDR Barclays Aggregate Bond shares are currently trading off about 0.4% on the day.