debt level is the debt as a percent of the total country's production, or GDP , which was $15.6 trillion as of the first quarter 2012 (the latest figures available). That means the debt-to-GDP ratio is now 102%, up from 51% in 1988. The Debt Ceiling: The U.S. also has a debt ceiling , which attempts to limit the debt. This is currently at $16.394 trillion. Not all the debt is subject to the debt limit -- right now, only $15.977 is. However, Congress usually raises the ceiling to prevent the negative consequences of a debt default . How The National Debt Affects the Economy: In the short run, the economy and voters benefit from deficit spending . In the long run, however, a growing Federal debt is like driving with the emergency brake on, further slowing the U.S. economy. That's because debt holders want larger interest payments to compensate for what they perceive as an increasing risk that they won't be repaid. This added interest payment expense usually forces a government to keep debt within reasonable limits. Over the next 20 years, the Social Security Trust Fund won't have enough to cover the retirement benefits promised to Baby Boomers. That means higher taxes, since the high U.S. debt rules out further loans from other countries. Unfortunately, it's most likely that these benefits will be curtailed, either to retirees younger than 70, or to those who are high income and therefore aren't as dependent on Social Security payments to fund