Per OECD for 2015, in U.S.$, for the 20 countries with the highest per capita health costs, the U.S. spent twice the average of the other 19 countries. As   a % of GDP for 2015, for the 20 countries with the highest expenditures, the U.S. spent 16.9% while the average of the lower 19 countries was 10.1%.

http://www.oecd.org/els/health-systems/health-statistics.htm

There's an old economics saying, "There ain't no such thing as a free lunch." We are all paying for more than we should for healthcare without a single payer system.