國債最多的10個國家

http://www.usnews.com/news/articles/2011/01/28/the-10-countries-with-the-most-debt

ref:
http://stats.oecd.org/Index.aspx?DataSetCode=GOV_DEBT
http://www.calvert.ch/maurice/2011/06/18/debt-and-gdp-accounting-for-population/