In trading on Tuesday, shares of the iShares Global Consumer Staples ETF ( KXI) entered into oversold territory, changing hands as low as $80.05 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 iShares Global Consumer Staples, the RSI reading has hit 28.9 — by comparison, the RSI reading for the S&P 500 is currently 34.1. A bullish investor could look at KXI'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), KXI's low point in its 52 week range is $70.97 per share, with $86.44 as the 52 week high point — that compares with a last trade of $80.09. iShares Global Consumer Staples shares are currently trading down about 1.1% on the day.