The DividendRank formula at Dividend Channel ranks a coverage universe of thousands of dividend stocks, according to a proprietary formula designed to identify those stocks that combine two important characteristics — strong fundamentals and a valuation that looks inexpensive. DTF Tax-Free Income Fund ( DTF) presently has an above average rank, in the top 50% of the coverage universe, which suggests it is among the top most "interesting" ideas that merit further research by investors.But making DTF Tax-Free Income Fund an even more interesting and timely stock to look at, is the fact that in trading on Tuesday, shares of DTF entered into oversold territory, changing hands as low as $14.25 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 DTF Tax-Free Income Fund, the RSI reading has hit 29.9 — by comparison, the universe of dividend stocks covered by Dividend Channel currently has an average RSI of 41.1. A falling stock price — all else being equal — creates a better opportunity for dividend investors to capture a higher yield. Indeed, DTF's recent annualized dividend of 0.84/share (currently paid in monthly installments) works out to an annual yield of 5.84% based upon the recent $14.39 share price.