Leaders In Gross National Debt As A Percent of GDP Among Advanced Economies In 2017

This comes from an IMF report. See IMF Fiscal Monitor: Capitalizing on Good Times, April 2018. You have to click on "Methodological & Statistical Appendix." Then click on "Full Text." Look for "Table A7. Advanced Economies: General Government Gross Debt, 2009–23
(Percent of GDP)."

Here are all the countries with at least 90%:

Country	% of GDP
Japan	236.4
Greece	181.9
Italy	131.5
Portugal	125.6
G7	118.6
Singapore	110.9
United States	107.8
Belgium	103.2
Cyprus	99.3
Spain	98.4
France	97

G7 means the average of Canada, France, Germany, Italy, Japan, the United Kingdom, and the United States.

They also have "Net Debt" as a percentage of GDP. The U.S. was at 82.3% in 2017 while the average for all Advanced Economies was 76.3%. For the G7 it was 87.5%.

From the report:

"Net debt: Gross debt minus financial assets corresponding to debt instruments. These financial assets are monetary gold and special drawing rights; currency and deposits; debt securities; loans, insurance, pensions, and standardized guarantee programs; and other accounts receivable. In some countries, the reported net debt can deviate from this definition based on available information and national fiscal accounting practices."

China is in the category of "Emerging Market and Middle-Income Economies." Their gross debt as a % of GDP was 47.8% in 2017. They don't have a report for their net debt.