The 2017 Long-Term Budget Outlook
https://www.cbo.gov/system/files/115th-congress-2017-2018/reports/52480-ltbo.pdf
Finds that U.S. federal debt held by the public is now at 77% of GDP, the highest level since shortly after World War II. If current laws remain unchanged, the debt will rise sharply over the next 30 years to 150% of GDP. The report also discusses the demographic and economic trends that underlie the long-term projections. From the Congressional Budget Office