GDP (Current Exchange Rate) Gross Domestic Product — GDP — may have its limits. But it's a useful, broad measure for looking at national economies. It's basically the total dollar value of all of the goods and services a country produces in a year.
Inside the World's Richest Rivalry Between Doris Duke and Barbara Hutton
World's Richest Man Picks Energy Miracles - Scientific American. It is pleasing to see those with resources are beginning to foster sustainable options & far-sightedness. We owe it to future generations to leave a legacy on which they too can build rather than a ravaged World with little future!