In trading on Thursday, shares of the Vanguard Long-Term Government Bond ETF (VGLT) entered into oversold territory, changing hands as low as $73.681 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 Vanguard Long-Term Government Bond, the RSI reading has hit 28.4 — by comparison, the RSI reading for the S&P 500 is currently 67.2.

A bullish investor could look at VGLT's 28.4 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), VGLT's low point in its 52 week range is $69.11 per share, with $82.00 as the 52 week high point — that compares with a last trade of $73.81. Vanguard Long-Term Government Bond shares are currently trading off about 0.9% on the day.