T he Bureau of Prisons (BOP) is the largest correctional agency in the country in terms of the number of prisoners under its jurisdiction. BOP must confine any offender convicted and sentenced to a term of imprisonment in a federal court. The total number of inmates under BOP's jurisdiction increased from approximately 25,000 in FY1980 to over 219,000 in FY2013. However, since the peak in FY2013, the number of inmates in the federal prison system decreased each subsequent fiscal year to approximately 192,000 inmates in FY2016. Appropriations for BOP

		Trends in BOP's Total Appropriations

As shown in Figure 1 , BOP's appropriations increased by nearly $7.149 billion from FY1980 to FY2016. BOP's funding decreased by $340 million in FY2017. Between FY1980 and FY2016, the average annual increase in BOP's appropriations was approximately $199 million. BOP's annual budget is divided between two major accounts: Salaries and Expenses (S&E) and Buildings and Facilities (B&F). First, while there has been a nearly continuous increase in the overall appropriations for BOP, it is in large part driven by an almost continuous increase in appropriations for BOP's Salaries and Expenses (S&E) account since FY1980 (see Figure 2 ). In general, appropriations for BOP's S&E account increased as the prison population increased, which is not surprising given that the S&E account funds the operation of the federal prison system, including the salaries and benefits of both correctional officers and other institutional employees. However, funding for the S&E account has continued to increase, albeit at a reduced rate, even though the prison population has decreased each fiscal year from FY2013 to FY2016. Requested Versus Enacted Funding for BOP

A comparison of BOP's annual appropriations for its S&E and B&F accounts to the Administration's request for both accounts shows that Congress has been more likely to fund the Administration's request for prison construction and less likely to fully fund the Administration's request for operating the federal prison system (see Figure 3 ). The data presented in Figure 3 show that from FY1980 to FY2017, Congress appropriated less than the Administration's request for the B&F account 16 times. Per Capita Cost of Incarceration

As noted above, appropriations for BOP have continued to increase even though the federal prison population has decreased in recent years. As show in Figure 4 , the nominal per capita cost of incarceration has increased from approximately $22,000 per inmate in FY2000 to almost $35,000 in FY2016, a 61% rise. From FY2000 to FY2012, the per capita cost of incarceration roughly increased at the same rate as inflation. However, since FY2013 increases in the per capita cost have started to outstrip inflation. Appropriations for BOP Relative to Those for the Department of Justice

One concern among some policymakers is that BOP's expanding budget is starting to consume a larger share of the Department of Justice's (DOJ) overall annual appropriations. The trend lines (the dashed lines in the figure) show that since FY1980, both BOP's total budget and the S&E account have, in general, encompassed a growing share of DOJ's annual appropriations.
The Bureau of Prisons (BOP) is the largest correctional agency in the country in terms of the number of prisoners under its jurisdiction. BOP must confine any offender convicted and sentenced to a term of imprisonment in a federal court.
Changes in federal criminal justice policy since the early 1980s spurred growth in the federal prison population. The total number of inmates under BOP's jurisdiction increased from approximately 25,000 in FY1980 to over 192,000 in FY2016. While the federal prison population in FY2016 is nearly 7 times larger than what it was in FY1980, the number of inmates under the BOP's jurisdiction peaked in FY2013 at approximately 219,000 inmates. The federal prison population has decreased each fiscal year from FY2013 to FY2016.
BOP's appropriations increased by nearly $7.149 billion from FY1980 to FY2016, which was the peak of BOP's nominal appropriations. Between FY1980 and FY2016, the average annual increase in BOP's appropriations was approximately $199 million. Its appropriations decreased by $340 million in FY2017.
BOP's annual budget is divided between two major accounts: Salaries and Expenses (S&E, i.e., the operating budget) and Buildings and Facilities (B&F, i.e., the capital budget).The nearly continuous increase in BOP's appropriations is in large part driven by a nearly unbroken year-by-year increases in the S&E account. Funding for the S&E account has continued to increase even though the prison population decreased from FY2013 to FY2016. An increasing per capita cost of incarceration might explain why funding for the S&E account has not decreased along with the prison population, but it might also be due to the fact that the prison population has not decreased to a point where BOP can reduce staff and shutter prisons.
The nominal per capita cost of incarcerating an inmate in the federal system has increased every fiscal year from FY2000 to FY2016, from approximately $22,000 per inmate to nearly $35,000 per inmate. After adjusting for inflation, the overall cost of incarceration was relatively flat from FY2000 to FY2012, but in recent fiscal years increases in per capita costs have started to outstrip inflation.
A comparison of requested and enacted funding for BOP's S&E and B&F accounts shows that Congress has been somewhat more likely to fund the Administration's request for prison construction and less likely to fully fund the Administration's request for operating the federal prison system. From FY1980 to FY2017, appropriations were lower than the Administration's request for the B&F account 16 times while appropriations were lower than the request for the S&E account 24 times.
One concern among some policymakers is that BOP's expanding budget is starting to consume a larger share of the Department of Justice's (DOJ's) overall annual appropriations. A review of funding for DOJ and BOP show that since FY1980 both BOP's total budget and the S&E account have, in general, encompassed a growing share of DOJ's annual appropriations.