Just over 25 years ago, when my 86-year-old mother was a sprightly 61, and working full time, Jimmy Carter called for the elimination of federal taxes on dividend income, as President Bush has just done. That was long before the great surge in stock ownership spawned by several Reagan-era tax changes, which enabled millions of Americans to set aside money for their senior years in individual retirement accounts (IRAs) and 401(k) investment plans. So President Bush’s proposal to end the double taxation on dividends should be welcome news to all of the estimated 84 million Americans who own stock, either directly or in retirement accounts. If they have children or stay-at-home or retired spouses, it should be good news to them as well. As a group, senior citizens should be the most thankful of all.