Looking at the universe of stocks we cover at Dividend Channel, on 8/8/13, Invesco Municipal Income Opportunities Trust ( OIA) will trade ex-dividend, for its monthly dividend of $0.035, payable on 8/30/13. As a percentage of OIA's recent stock price of $6.12, this dividend works out to approximately 0.57%, so look for shares of Invesco Municipal Income Opportunities Trust to trade 0.57% lower — all else being equal — when OIA shares open for trading on 8/8/13.Below is a dividend history chart for OIA, showing historical dividends prior to the most recent $0.035 declared by Invesco Municipal Income Opportunities Trust: In general, dividends are not always predictable; but looking at the history above can help in judging whether the most recent dividend from OIA is likely to continue, and whether the current estimated yield of 6.86% on annualized basis is a reasonable expectation of annual yield going forward. The chart below shows the one year performance of OIA shares, versus its 200 day moving average: Looking at the chart above, OIA's low point in its 52 week range is $6.10 per share, with $8.02 as the 52 week high point — that compares with a last trade of $6.12. According to the ETF Finder at ETF Channel, OIA makes up 1.01% of the CEF Municipal Income ETF ( XMPT) which is trading relatively unchanged on the day Tuesday. In Tuesday trading, Invesco Municipal Income Opportunities Trust shares are currently off about 0.5% on the day.