for many years the united states produced more than 90% of the commercial helium in the world. in the mid-1990s, a new plant in arzew, algeria, began producing 17 million cubic meters (600 million cubic feet), enough to supply all of europe's demand. in 2004–2006, two additional plants, one in ras laffan, qatar, and the other in skikda, algeria, were built, and algeria became the second leading producer of helium.