In trading on Monday, shares of the PowerShares Dynamic Media Portfolio ETF ( PBS) entered into oversold territory, changing hands as low as $23.6801 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 PowerShares Dynamic Media Portfolio, the RSI reading has hit 29.2 — by comparison, the RSI reading for the S&P 500 is currently 47.6. A bullish investor could look at PBS's 29.2 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), PBS's low point in its 52 week range is $18.80 per share, with $26.89 as the 52 week high point — that compares with a last trade of $24.03. PowerShares Dynamic Media Portfolio shares are currently trading off about 1.2% on the day.