Looking at the universe of stocks we cover at Dividend Channel, on 5/15/13, AGL Resources Inc. ( GAS) will trade ex-dividend, for its quarterly dividend of $0.47, payable on 6/1/13. As a percentage of GAS's recent stock price of $43.22, this dividend works out to approximately 1.09%, so look for shares of AGL Resources Inc. to trade 1.09% lower — all else being equal — when GAS shares open for trading on 5/15/13.Below is a dividend history chart for GAS, showing historical dividends prior to the most recent $0.47 declared by AGL Resources Inc.: In general, dividends are not always predictable; but looking at the history above can help in judging whether the most recent dividend from GAS is likely to continue, and whether the current estimated yield of 4.35% on annualized basis is a reasonable expectation of annual yield going forward. The chart below shows the one year performance of GAS shares, versus its 200 day moving average: Looking at the chart above, GAS's low point in its 52 week range is $36.59 per share, with $44.32 as the 52 week high point — that compares with a last trade of $43.24. According to the ETF Finder at ETF Channel, GAS makes up 2.17% of the High Yield Equity Dividend Achievers Portfolio ETF ( PEY) which is trading lower by about 0.1% on the day Monday. In Monday trading, AGL Resources Inc. shares are currently down about 0.8% on the day.