11. A report from the Congressional Budget Office (CBO) notes, "Potential GDP is CBO's estimate of the maximum sustainable output of the economy." In early 2015, the CBO estimated that the gap between real GDP and potential GDP would fall from 2.9 percent in 2014 to zero in 2017. In 2014, real GDP was $16.3 trillion and the CBO's estimate of potential GDP was $16.8 trillion. The CBO forecast that potential GDP would increase to $17.5 trillion. Sources: Congressional Budget Office, "The 2015 Long-Term Budget Outlook," June 2015, p. 36; and Congressional Budget Office, "The Budget and Economic Outlook: 2015 to 2025," January 2015. The CBO includes the word "sustainable" in its definition of potential GDP because

Fig: 1

Fig: 2