As of October 1st of 2007 (the start of the 2008 Federal Government fiscal year), federal debt stood at $9 trillion and 70 billion. In the subsequent ten years and nearly five months, the US federal debt has grown $11 trillion and 785 billion and now stands at $20 trillion and 855 billion (chart below). Over the same period, US GDP grew $5 trillion and 169 billion.
Simply put, for every $1 of new federal debt undertaken, the US achieved $0.44 cents of economic activity or "growth". However, as the chart below shows, the huge increase in federal debt (red line) was accompanied by a minimal increase in interest payable on all that debt (blue line). The boxes detail the total debt incurred during each period against the annual increase in interest payments on that additional debt. The Federal Reserve is primarily to thank for the cheapening of debt and encouragement to undertake all that debt, but many fear the same Fed is set to hike those interest payments with its ongoing rate hikes.https://www.zerohedge.com/news/2018-03-02/faster-america-grows-faster-america-goes-bust