In Australia, England, and the United States, it's 100% propane. In New Zealand and Belgium, it's 60% propane and 40% butane. In India, Spain, and Hungary, it's 35% propane and 65% butane. In Greece, it's 20% propane and 80% butane. Butane does not vaporize well at colder temperatures, so the ratio typical to each country really depends on climate. Some even change the ration based on the season. But it is never less than 20% propane.